Psychological improvements include the reduction of depression, anxiety, and stress. Ethno-medicinal study on the traditional herbal knowledge of the tiwa Weber W, Newmark S. The report documented important differences in disease prevalence and severity by sociodemographic characteristics that public health officers, the dental profession, and the community should consider in implementing interventions to prevent and control disease and to reduce the disparities observed. Identify the available body of evidence and experience in using prebiotic fiber in infants with inborn errors of metabolism. Even areas of nature that are critical to our very survival are at risk by the hands of those who would experiment with our futures in the name of higher corporate profits.
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Cardiac rehabilitation provides many benefits for patients. The most important of these are discussed in this section. Cardiac rehabilitation exercise training for patients with coronary heart disease or congestive heart failure CHF leads to objectively verifiable improvement in exercise capacity in men and women, regardless of age.
The nonfatal infarction rate is 1 patient per , patient-hours; the cardiac mortality rate is 1 patient per , patient-hours.
The benefits are even greater in patients with diminished exercise tolerance. This beneficial effect does not persist long-term after completion of cardiac rehabilitation without a long-term maintenance program. Therefore, exercise training must be maintained long-term to sustain the improvement in exercise capacity. In patients with coronary heart disease, angina significantly improves during the cardiac rehabilitation exercise program.
Objective evidence of improvement in ischemia has been seen by performing interval stress ECG or radionuclide testing. Similarly, patients with LV failure or dysfunction show improvement in the symptoms of heart failure. Improvements in lipid and lipoprotein levels are observed in patients undergoing cardiac rehabilitation exercise training and education.
Exercise training as a sole intervention has an inconsistent effect on controlling excess weight. Optimal management of obesity requires multifactorial rehabilitation, including nutritional education and counseling, behavioral modification, and exercise training.
Rehabilitation exercise training as a sole intervention has minimal effect; however, multifactorial intervention has been shown to have beneficial effects. Inconsistencies with this theory remain unresolved. Cardiac rehabilitation services with well-designed educational, counseling, and behavioral modification programs result in cessation of smoking in a significant number of patients.
This reduction is combined with the spontaneously high smoking cessation rates following acute coronary events. Cardiac rehabilitation exercise and educational services enhance measures of psychological and social functioning.
In multifactorial cardiac rehabilitation programs, improvement in emotional-stress measurements occurs, as does a reduction of type A behavior patterns. This reduction of stress is consistent with improvement in psychosocial outcomes that occurs in nonrehabilitation settings.
Cardiac rehabilitation exercise training exerts less influence on rates of return to work than on other aspects of life. Many nonexercise variables also affect this outcome eg, prior employment status, employer attitude, economic incentives.
Scientific data suggest a survival benefit for patients who participate in cardiac rehabilitation exercise training, but it is not attributable to exercise alone. This survival benefit is due to multifactorial interventions. The scientific evidence pertaining to the relationship between cardiac rehabilitation exercise training and mortality also includes scientific reports that have appeared on the US National Institutes of Health Web site. This beneficial outcome persisted at the year follow-up.
When combined with intensive dietary intervention, with or without lipid-lowering drugs, exercise training may result in the limitation of progression or in the regression of angiographically documented coronary atherosclerosis. Exercise training in patients with heart failure and compromised LV ejection fraction produces favorable hemodynamic changes in the skeletal musculature. Therefore, cardiac rehabilitation exercise training is recommended for the improvement of skeletal muscle functioning.
However, such training does not seem to improve cardiac hemodynamic function or collateral circulation to any significant degree. Following orthotropic cardiac transplantation, rehabilitation exercise training is recommended to improve patients' exercise tolerance measurements.
Coronary patients who are elderly have exercise trainability comparable to that of younger patients participating in similar rehabilitation programs. Elderly patients male and female show comparable improvements.
Unfortunately, referrals to cardiac rehabilitation are made less frequently for elderly patients, particularly for elderly women; participation in cardiac rehabilitation also is less frequent among the elderly. No complications or adverse outcomes for elderly patients have been described in any study. Elderly male and female patients should be encouraged to participate in cardiac rehabilitation. Patients who are on renal dialysis are at high risk for cardiac death and have a large burden of cardiovascular disease and cardiovascular disease risk factors.
Cardiac rehabilitation can promote improved survival of nondialysis patients after coronary artery bypass grafting CABG surgery and is covered by Medicare, [ 20 ] but no studies have investigated whether dialysis patients' survival after CABG may be improved as a function of cardiac rehabilitation. Women and black patients aged 65 or older, along with lower-income patients of all ages, were significantly less likely to receive cardiac rehabilitation services.
This observational study suggests that following CABG, cardiac rehabilitation increases a dialysis patient's likelihood of survival. Overview Exercise training involves certain risks, especially in patients with undiagnosed or undertreated myocardial ischemia, ventricular arrhythmias, or LV dysfunction.
The intensity of exercise must be kept below the level of exercise at which the abnormalities were elicited during the risk stratification and testing phase. The proper selection of patients is of paramount importance before phase 2 or phase 3 exercise programs are begun.
Patients also must be monitored with continuous electrocardiography and be supervised closely. High-risk factors include the following:. Severe exercise-induced ischemia such as angina at a workload of less than 5 METs , ST-segment depression of greater than 0. Complex ventricular arrhythmias, such as nonsustained ventricular tachycardia a less than second run of ventricular tachycardia [VT] at rest or with exercise or a history of previous sudden cardiac arrest SCA.
Hypotensive response to exercise ie, drop in systolic pressure of more than 20 mm Hg at incremental exertion. Low functional capacity ie, peak workload of less than 5 METs, functional capacity determined by CPX testing with reduced peak oxygen [VO 2 max] consumption. For some patients, the risks of exercise may outweigh the benefits.
In these instances, patients should be counseled against exercise training, and their medical management must first be optimized with thorough supervision. The group of high-risk patients described above constitutes the bulk of such patients. Intermediate-risk patients need somewhat less intense surveillance.
The level of supervision needed includes unmonitored exercise training in groups in the presence of health professionals who are certified in advanced cardiac life support ACLS. Very low-risk patients can exercise safely and independently once they have learned how to monitor their pulse rates and are able to recognize warning signs.
Such patients have greater than 8 METs of exercise capacity without symptoms or signs of angina, heart failure, or arrhythmias. Alternative approaches to the traditional supervised cardiac rehabilitation programs have been evaluated and found to be reasonably safe.
These off-site, self-monitored or telemetry-monitored programs are applicable primarily to very low-risk patients and include 1 home-based cardiac rehabilitation effective and safe and 2 exercise with trans-telephonic surveillance. Supervised exercise training programs have extremely good safety records, despite the inherent potential for cardiovascular complications during exercise.
None of the more than 3 dozen randomized controlled trials of cardiac rehabilitation exercise testing and training in patients with coronary heart disease, involving over 4, patients, showed any increase in morbidity or mortality in rehabilitation compared with control patient groups.
A survey of US cardiac rehabilitation programs reported a low rate of nonfatal myocardial infarction MI; 1 case per , patient-hours and cardiac mortality 1 case per , patient-hours. A total of 21 episodes of cardiac arrest occurred, with resuscitation successfully performed in 17 of these episodes. Therefore, the safety of exercise within cardiac rehabilitation programs is well accepted and established.
Cardiac rehabilitation, a clinically effective intervention for coronary heart disease, has been subjected to preliminary cost analyses. Research therefore indicates that cardiac rehabilitation is not only clinically effective, but is cost-effective as well.
Cardiac rehabilitation compares favorably with other medical interventions performed commonly in patients with coronary heart disease.
Cardiac rehabilitation is an important component of the current multidisciplinary approach to the management of the patients with various presentations of coronary heart disease. Cardiac rehabilitation involves exercise training, education, counseling regarding risk reduction and lifestyle modification, and, frequently, behavior interventions.
The goals of cardiac rehabilitation services are to improve the physiologic and psychosocial condition of patients. Physiologic benefits include the improvement of exercise capacity and the reduction of risk factors eg, cessation of smoking and lowering of lipid levels, body weight, blood pressure, blood glucose , with the exercise component provided through rehabilitation possibly reducing the progression of atherosclerosis. Psychological improvements include the reduction of depression, anxiety, and stress.
All of these improvements enable the patient to acquire and maintain functional independence and to return to satisfactory and appropriate activity that benefits the patient and society.
Contribution of patient and physician factors to cardiac rehabilitation referral: Nat Clin Pract Cardiovasc Med. Modest effects of exercise training alone on coronary risk factors and body composition in coronary patients.
Effects of exercise and cardiac rehabilitation on cardiovascular outcomes. Med Clin North Am. Changes in cardiorespiratory fitness, psychological wellbeing, quality of life, and vocational status following a 12 month cardiac exercise rehabilitation programme.
Cardiac rehabilitation in the elderly: Am J Geriatr Cardiol. Cardiac rehabilitation and preventive cardiology in the elderly. Benefits of cardiac rehabilitation and exercise training in older persons.
Taylor R, Kirby B. Cost implications of cardiac rehabilitation in older patients. Int J Clin Pract. The cardiac model of rehabilitation for reducing cardiovascular risk factors post transient ischaemic attack and stroke: Cardiac rehabilitation and outcome in stable outpatients with recent myocardial infarction.
Arch Phys Med Rehabil. Postacute Rehabilitation After Coronary Surgery: Am J Phys Med Rehabil. Walking tests during the exercise training: Specific use for the cardiac rehabilitation. Ann Phys Rehabil Med. Determining the minimal clinically important difference for the six-minute walk test and the meter fast-walk test during cardiac rehabilitation program in coronary artery disease patients after acute coronary syndrome.
J Cardiopulm Rehabil Prev. Cardiac rehabilitation improves the ischemic burden in patients with ischemic heart disease who are not suitable for revascularization.
Comparison of the clinical profile and outcome of women and men in cardiac rehabilitation. Depression predicts failure to complete phase-II cardiac rehabilitation.
Heart rate recovery in heart failure patients after a week cardiac rehabilitation program. Pre- and postoperative cardiopulmonary rehabilitation in hospitalized patients undergoing coronary artery bypass surgery: Carrel T, Mohacsi P. Optimal timing of rehabilitation after cardiac surgery: Patients with Diabetes in Cardiac Rehabilitation: Attendance and Exercise Capacity. Med Sci Sports Exerc. Lifestyle change diminishes a hypertensive response to exercise in type 2 diabetes.
Favourable effects of exercise-based cardiac rehabilitation after acute myocardial infarction on left atrial remodeling.
Changes in lipid profile of patients referred to a cardiac rehabilitation program. Eur J Cardiovasc Prev Rehabil. Clinical profile and outcomes of obese patients in cardiac rehabilitation stratified according to National Heart, Lung, and Blood Institute criteria. Cardiac rehabilitation and survival of dialysis patients after coronary bypass. J Am Soc Nephrol. Is physical training contraindicated in patients with deep vein thrombosis during cardiac rehabilitation?.
Monaldi Arch Chest Dis. Program participation, exercise adherence, cardiovascular outcomes, and program cost of traditional versus modified cardiac rehabilitation. Metabolic syndrome in patients with intermittent claudication referred to vascular rehabilitation.
A statement for healthcare professionals from the American Heart Association. Rehabilitation of patients with coronary artery disease. A Textbook of Cardiovascular Medicine.
Prevention of myocardial reinfarction. Recommendations based on results of drug trials. Probiotics, Antifungals, and Digestive Enzymes Probiotics and antifungals are common treatments for the abdominal pain, bloating, gas, constipation, gastroesophageal reflux disease, nausea, vomiting, and diarrhea that many ASD patients experience.
No conclusive evidence is available to explain why these digestive symptoms are common in ASD patients, but the use of probiotics has provided relief of these symptoms for many of them. The National Center for Complementary and Alternative Medicine defines probiotics as live microorganisms—usually bacteria, but they also can include microbes such as yeast—that people can ingest to increase the population of desirable bacteria in the gut.
Antifungals inhibit the growth of a fungus or destroy it. It can cause itching and burning of the mucous membranes, skin eruptions, and imbalances in the overall health of the gastrointestinal tract. Digestive enzymes are substances that help break down large macromolecules in foods to smaller substances to facilitate their absorption.
Examples of digestive enzymes include proteases that break down proteins or lipases that help break down fat. If a dietitian suspects a patient is experiencing inadequate digestion, digestive enzymes may help. In some cases, digestive enzymes may aid in the removal of toxic compounds from the gut. Research has shown that eliminating gluten and casein from the diet of ASD patients can alleviate symptoms such as behavior problems and poor cognitive and social functioning.
There are several theories as to why the elimination diet may be beneficial. These two peptides, which appear to have a chemical structure similar to opiates, can cross the blood-brain barrier and cause symptoms such as delayed social and language skills, and withdrawn behavior.
The exclusion of wheat and milk puts an ASD patient at risk of nutrient deficiencies in calcium, protein, vitamin D, folic acid, and B vitamins. And studies have found that diets lacking gluten and casein raise the risk of decreased bone density and stunted growth. A more complex elimination diet that some specially trained dietitians use is called the LEAP Lifestyle, Eating, and Performance protocol. This involves eliminating any known foods or chemicals suspected of triggering symptoms.
These foods and chemicals are identified by a blood test called the Mediator Release Test, which shows reactions to multiple foods and chemicals. Some of the mediators released include histamine, prostaglandins, leukotreines, cytokines, and peroxides. These mediators have been shown to cause reactions such as inflammation, diarrhea, pain, intestinal cramping, constipation, headache, and pain receptor changes.
Studies have shown enhanced proinflammatory cytokine production is present in patients with ASD. Reactions to certain foods and chemicals also can cause the release of the brain neurotransmitters dopamine and serotonin.
Dopamine appeals to the sense of reward and enjoyment, and plays a role in addictive behavior. Serotonin contributes to feelings of well-being and happiness. According to certified LEAP therapists, ASD patients also may feel euphoric after ingesting a reactive substance or stop throwing a tantrum after eating a reactive food.
Contacts with other healthcare disciplines that monitor patient behaviors make RDs invaluable as they provide holistic approaches to treatment for optimal cognitive and social functioning. RDs are the best source for providing accurate and up-to-date information on supplementation, elimination diet therapy, and current research on new nutritional approaches.
More and more patients will depend on dietitians as the source of information that will enable patients to live productive lives. Dietitians with the passion to work with this challenging segment of the population will be a much-needed resource in the dietetics community in the years to come.
Learning Objectives After completing this continuing education activity, nutrition professionals should be able to:. CPE Monthly Examination 1. The patient may have which type of autism spectrum disorder ASD? Pervasive developmental disorder, not otherwise specified d. None of the above.
Which of the following is not usually a challenge ASD patients may face that often leads to poor diet quality? Patients with ASD who avoid several types of food, such as protein, usually will accept foods in the carbohydrate group.
Which of the following is one of the best approaches to addressing problem-eating behaviors? Introduce one new food every three weeks until the child gets accustomed to eating it.
Evaluate the foods the child agrees to eat for potential deficiencies. Which of the following supplements have been shown to reduce anxiety and aggression, decrease hyperactivity and impulsivity, and increase attention span in ASD patients?
Omega-3 fatty acids c. Which of the following treatments may aid in removing toxic compounds from the gut of ASD patients? Poor cognitive functioning c. Poor social functioning d. All of the above. Significant delays in language skills b. Abnormal responses in balance c. Delayed reactions to pain d. A near genius IQ. A viral infection such as the flu in the third trimester has been shown to triple the odds of a child developing ASD.
Which of the following is not an early sign of ASD in infants? Not wanting to cuddle b. Lack of eye contact c. Abnormal responses to touch and affection d. The Johns Hopkins Medicine website. Accessed December 4, Reviewed May 29, Accessed August 21, National Autism Association website. Centers for Disease Control and Prevention website. Updated March 29, Accessed April 20, Chlorpyrifos dursban -associated birth defects: Mercury exposure, nutritional deficiencies, and metabolic disruptions may affect learning in children.
Sorting out the spinning of autism: Acta Neurobiol Exp Wars. This information is then expressed at the level of the population group concerned, in the form of prevalence rates, in other words, percentages of individuals who are well- or malnourished with respect to the form of malnutrition considered, in accordance with cut-off values chosen. The use and interpretation of these indicators of status are presently well-established.
Nevertheless, it is useful to consult a specialist for selecting and interpreting them, as these indicators can reflect, for example, either a likely risk simple deviation from a norm or a real risk of nutrient deficiency recognised functional deficit , either a recent or old, acute or chronic history of undernutrition wasting, stunting in the young child.
Some indicators are useful at population level rather than at individual level. Finally, some will be more useful than others for anticipating the benefit of a possible intervention. Once the nutritional status of the population and its geographical or socio-economic distribution are known, and goals for improvement have been set, information is needed on the determinants of the situation; in other words, on the factors, events or characteristics which are likely to affect the nutritional status of individuals within the population at different levels.
It will then be possible to define a strategy seeking to alter a number of these factors to improve the situation as reflected in the stated objectives. This sector includes a wide range of potential indicators covering agricultural production, food marketing and food consumption.
A number of them are regularly collected by the information systems operated by Ministries of Agriculture and Trade. Environmental hygiene aspects encompass water supply, and supply of healthy food products, sanitation in a broad sense, and the life-styles of the populations themselves; health-related aspects include the sphere of infectious and parasitic diseases on the one hand, and that of health care systems, their coverage and utilization, on the other. In general, relevant departments of the Ministries of Health collect the corresponding indicators; a number of them have formed the basis for the health information systems launched in connection with the implementation of the policy of primary health care in the s, which was updated in WHO ; a.
The concept of "caring" relates to both caring at family level and broader aspects of social solidarity and protection at the community or national level. It thus covers the whole range of mother-and-child caring practices, since mothers and infants are the main groups at risk, but also includes attitudes and practices of other household or community members towards those most vulnerable socially regarding time available, food distribution, emotional and material support and the level of education of care providers in general.
Indicators of this type are seldom collected regularly, when they do exist, they tend not to be easily accessible on a clearly identified central level. Thus the available information usually has to be complemented through specific community surveys, focusing especially on qualitative aspects. Yet the most fundamental causes of malnutrition and mortality very often lie outside the field of nutrition and the chains of causes briefly reviewed above: Fundamental agro-ecological and socio-economic indicators therefore also need to be included in any causal analysis of a nutrition situation at national level.
They are generally available from the major Ministries, particularly those in charge of planning. Designing a programme consists of defining material and human resources to be mobilised, in what way, for what purpose, and how, ultimately, this will alter the initial situation.
Monitoring these policies and programmes will therefore require three different types of evaluations , namely monitoring implementation of programmes, evaluation of programme impact, and, keeping track of general trends in the nutritional situation. This deals with the assessment of programme activities, in other words the extent to which operational objectives are met.
Indeed, in order to make sure that the programme contributed to changing the situation, we must first know whether it was implemented according to plans. This assessment is based on indicators of programme implementation developed from the conception of the programme and monitored for partial or full achievement at each stage of the programme.
Programmes are composed of a series of operations, each with a specific goal. To each operation corresponds a set of indicators whereby the quantity or quality of the operation can be assessed. Under a programme to promote healthier life-styles and eating habits, a country has decided to implement activities to produce training material and to carry out educational campaigns.
The implementation indicators that were adopted focused on the number and quality of educational materials produced, the number of training workshops held and teachers thus recruited, and the number of promotion campaigns carried out, associations set up and situation reports produced by those in charge throughout implementation of the programme, etc.
These indicators may concern the extent to which the target population is covered by the programme, the number of training sessions organized, the percentage of households who benefited from access to the various services set up for them, etc. In general, these indicators are specific and easy to identify, if the activities to be accomplished, which they should reflect, have been correctly defined; they are completely dependent on the specific operational aspects of the programme and therefore cannot be defined independently, in advance, based on a general framework.
Extensive use is therefore made of qualitative indicators inasmuch as the quality of activities is measured as well as their level of implementation. This type of assessment and the corresponding implementation indicators are outside the scope of this guide. Indicators of outcomes and of impact are used here in order to measure the effectiveness of the programme - its ability to modify the situation at the beneficiary level - as well as any possible undesired effects, whether anticipated or not.
The evaluation of a programme is commonly based on a longitudinal comparison of indicators before and after implementation of the programme before-after comparison. However, unless the programmes are highly specific and narrowly targeted, interpretation may be difficult, since factors other than those introduced or changed by the programme known as confounding factors may have varied at the same time and contributed to the apparent effect of the programme.
If conditions fluctuate over time change of climatic conditions, food production varying from one year to another , if the measurements are carried out at very long intervals, or if the planned intervention is general in nature, attributing the effects observed to the programme alone becomes increasingly difficult.
In the framework of a programme aimed at reducing the prevalence of undernutrition, analysis of the context revealed that diarrheal diseases were one of the main associated factors.
A sub-programme was therefore set up to reduce the incidence of diarrheal diseases among young children. One of its components was the use of oral rehydration solution ORS , and the other involved an information campaign on how to improve environmental hygiene. One of the undesirable effects that the programme had to assess was the risk that the rehydration solutions would be prepared incorrectly or unhygienically. Concerning improvements in environmental hygiene, the programme recorded indicators relating to: Changes achieved in terms of health status reduction in the incidence of diarrhea per child per year, improvement in the nutritional status of young children were selected as final impact indicators.
If the programme consists of scaling up an intervention that has proved effective elsewhere, at experimental level, the causal interpretation is simplified. If it is based on strong, but as yet unverified, hypotheses, it is more difficult to automatically attribute the observed effects to the intervention . Insofar, however, as indicators of different confounding factors likely to influence the situation were recorded before and after the implementation of the programme, statistical adjustments may be used during the analysis to improve interpretation - hence the importance of collecting these additional indicators.
A with-without comparison can then be made between two areas, one benefiting from the programme and the other not external control group. This poses the problem of initial comparability of the two areas: Alternatively, two areas may be compared with an unequal level of implementation of the programme internal control group or, more simply still, groups of individuals or households may be compared which have not benefited of the programme at the same level, since the level to which target individuals are reached by programmes is generally variable.
Ideally, the impact evaluation should follow an experimental design, with randomization of the individuals or areas to receive or not the intervention. This is the most rigorous way to proceed in order to be able to conclude on the actual impact of the intervention. In most cases, an impact evaluation of the crude effect will be quite acceptable, i. Elements suggesting a cause and effect relationship can be formulated, but without seeking absolute proof, if plausibility of the effectiveness of the programme appears sufficient to those in charge.
In , Vietnam implemented a national strategy of supplementation with vitamin A capsules through health centres to combat xerophthalmia. Three years later, an evaluation recorded a very high coverage of the populations at risk by the programme and, in addition, did not observe any clinical case of xerophthalmia based on a nationally representative sample of pre-school children.
In this case, there is little doubt that the result is directly linked to the programme, even if the evaluation cannot formally prove it: Plausibility of the link is very strong here. On the other hand, during the same period another country launched a programme to improve household food security, encompassing a certain number of measures such as the support to farm-gate prices for food crops and a reorganization of local markets on the basis of previously identified weaknesses.
The evaluation of the programme after several years of operation showed a slight improvement in the situation. Without a rigorous evaluation design, it is impossible to evaluate the relative share of improvement due to the programme or to other factors. These elements will be useful each time it has to be decided whether the programme should be continued or not.
A group of convergent elements based on the available indicators will be established in order to reach a conclusion on its likely effectiveness. Often, for financial reasons, a programme cannot be implemented straight away in all the targeted areas; these will be incorporated into the programme gradually. However, the necessary indicators can usefully be collected in all the zones from the start, for this will provide elements for comparisons between zones with and without the programme and before and after the programme, which will in turn be useful to document the plausibility of effectiveness of the intervention.
This will make it easier to evaluate the sustainability of the programme by measuring the effect simultaneously in areas where the programme has been in operation for increasing durations. The purpose of an evaluation is not only to measure impact, but also to allow the programme to be adapted to changing conditions. An early warning system will be evaluated primarily on its ability to foresee any worsening in the consequences of food crises among the groups most at risk; it will thus comprise a number of indicators on the strategies implemented according to the degree of vulnerability, on the levels of food consumption and on the nutritional status of these groups, for example.
However, it will also involve indicators to assess whether the situation is evolving towards greater stability improvement of climatic conditions or of food production, for example so that the primary objective of the programme can be refocused if the initial goal has become obsolete. When evaluating programmes, a distinction is made in practice between impact which is the direct result of the programme, and longer term benefits, which encompass the indirect effects of the programme on the target population, or indeed the whole population, in terms of health, economic and social situation.
In the case of an isolated programme, attention may be focused on its specific impact, but in the context of overall monitoring of a policy or group of programmes, the impact of the complete set of strategies will be the subject of regular evaluation - which will aim not so much at providing evidence of the effectiveness of one or another programme, but rather at verifying whether the situation is evolving in the desired direction, taking into account external circumstances and the programmes in operation.
Apart from regular measurement of progress, this will also provide an opportunity to check that the conceptual analysis on which the choice of different strategies was based is still relevant, or to see whether activities need refocusing. The aim is to examine changes in the situation in terms of the general objectives of the policy adopted, implying regular collection of a certain number of indicators of risk and of causes, as well as major basic indicators, to be used by country planners and by international agencies or donors, and assessment of trends.
This corresponds to one of the nine strategies proposed in by the ICN Plan of Action - which has been taken up since then by a number of countries for their national action plan - that of "assessing, analysing and monitoring nutrition situations".
This implies setting up a proper nutrition surveillance system applied to planning. These national plans have explicit general goals with an order of magnitude for expected reductions in malnutrition levels or improvements in various sectors. As a result of its plan, Ecuador, like other countries, anticipates fulfilling the following objectives in terms of improvements in the nutritional status of the population: Objectives will be all the more explicit and realistic if there is a recent "baseline" and an idea of trends in the past or in neighbouring countries or in countries with similar constraints.
However, waiting for a complete baseline to be available would not be reasonable; one can start with existing data from the various services, or with rapid surveys carried out on a one-off basis when there are no data for a specific problem deemed to be important. Yet implementing a policy must be an opportunity for also setting up a monitoring system - covering at least the main indicators of status and causes of malnutrition, which will be put in perspective with major agro-ecological and socio-economic indicators - in order to have an ongoing "log-book" of the situation and of time trends.
After analysis, a country considers that the prevalence of low birthweight is too high and that the goal of reducing it implies i strengthening the performance of pre-natal health care services, ii promoting a better diet for mothers-to-be, either through better use of local food or the specific distribution of food supplements, and iii encouraging a reduction in the workload of pregnant women through various measures.
The precise actions to be undertaken and any precise quantification in terms of intermediate objectives depend of course on the specific country situation.
Monitoring implementation of these actions will be based on a quantitative and qualitative assessment of the performance level of the units concerned number of rations distributed or number of persons who have used the services, percentage of services which have given advice and care of adequate quality to pregnant women, quality of rations distributed, level of use of the advice and care by the beneficiaries, etc.
At programme evaluation, outcomes and impact indicators can be based on changes in the frequency of consumption of certain foods by the women attending the units, or on changes in average birth weight and prevalence of low birth weight in the target population.
Indicators do not all have the same value. In theory this depends on their ability to best reflect a sometimes complex reality, but a trade-off will have to be found given the level of difficulty in collecting them. Therefore, indicators are traditionally defined according to a certain number of properties that allow their value to be assessed, at least in a given context.
Obviously they do not all present all the characteristics of a good indicator, so that it will have to be decided which characteristics are to be given priority when selecting indicators. It entails that the indicator does indeed offer a true and as direct as possible measurement of the phenomenon considered. At conceptual level, it depends first of all on how clearly the phenomenon to be measured has been defined and also on the ability to measure it directly. This poses a problem where the phenomenon to be measured is linked to a multidimensional concept, and is thus difficult to measure in a global way.
There must, in particular, be a consensus on the level and significance of cut-off points for classification. A major standardization effort has for example been made in the field of measuring nutritional status and recommended dietary intakes, and this has helped give a more precise framework for use of the corresponding indicators.
This is not always the case in other sectors, either because the indicators lend themselves less to quantification, or because such quantification depends very much on local circumstances. Relevance in the context of planned use must, in this case, be based on a local analysis shared among the different stakeholders, as we will see below. Moreover, even if the indicator correctly describes a phenomenon, any systematic bias in collecting the corresponding information due to measurement methods or instruments will affect its validity.
There is no overall indicator to provide a picture of "nutritional status", therefore a decision has to be made on which specific aspect of nutritional status is to be characterized: Even in the case of energy status, for example, no overall indicator is available; the indicator which is the most relevant for the aspect one wishes to prioritise - physical, biochemical, functional, etc.
For assessing the nutritional situation of a population, a set of individual anthropometric measurements have been adopted, that, when compared to reference values, make it possible to assess the status of individuals or populations; they constitute the corpus of relevant indicators to be used preferably over any other. However, when using these indicators, one should be aware of limitations to their validity: In the field of "food security", - again a very broad concept difficult to translate in simple terms - there is a considerable number of indicators, each reflecting a specific aspect and thus only relevant for a given aspect.
For example, in order to describe the level of food insecurity of a household, an indicator based on a quantitative criterion of food consumption or a qualitative criterion of the perception by the household of its own food insecurity situation will be more relevant than an indicator of prices of foodstuffs on the local market.
Imprecision due to measurement methods, variability from one day to another may limit the reproducibility of the indicator. This causes an increase in variance and implies that larger samples will be needed in order to assess correctly the level of the indicator and its variations over time. Subjectivity bias is a frequent risk with indicators deriving from qualitative surveys, as they describe behaviours or opinions of households, for example, since the personality or technique of the person conducting the survey may influence the nature of responses.
Moreover, respondents to a questionnaire or subjects under observation can modify their responses or behaviour in a normative way. People who are overweight, for example, often minimise their actual food intake when interviewed for a food consumption survey.
Reproducibility guarantees that an indicator can be measured at repeated intervals in a comparable manner - a quality which is crucial when using the indicator to assess and monitor the situation. A complementary characteristic is specificity, which refers to the ability to identify those not affected by the risk or characteristic. Sensitivity is measured in practice by the ratio of the number of individuals identified by the indicator as being at risk or as having the characteristic to the number of individuals who are actually at risk or have the characteristic.
Specificity is the ratio of the number of individuals not identified by the indicator to the number of individuals who are actually not at risk or do not possess the characteristic. Sensitivity thus gives an idea of the degree of correct or misclassification linked to the use of an indicator. Not all indicators lend themselves to an assessment of sensitivity. Sensitivity applies essentially to indicators with cut-off values.
Moreover, sensitivity is measured with respect to a given goal; sensitivity of an indicator such as weight-for-height at a given cut-off value will not be the same, depending on whether the goal is to identify children who are wasted or those who are at risk of dying in coming months. Data for quick computation of these parameters sensitivity, specificity are not always available, so in practice, reference is made to existing data from the literature to find those closest to the chosen cut-off values and expected prevalences.
One particular aspect of sensitivity is the ability of an indicator to measure change, not in order to identify or target a particular category of individuals as previously but to detect the smallest possible change in the phenomenon described, in a significant way. While sensitivity, in general, is important when establishing a baseline, and for defining the target groups to which the activities will be directed, this ability for measuring change is crucial for assessing or monitoring trends, in particular to detect changes in the situation during implementation of the programme.
However, it is relatively inert when assessing small progressive changes in nutritional status over time, and the weight-for-height indicator will be preferred in this case, since it is more sensitive to change. Also, urinary iodine will respond to introduction of salt iodization in a region quicker than prevalence of goitre, which will decline only slowly.
In addition to these inherent characteristics of indicators, their operational value should be examined; it will be essential when the choice of indicators is made, especially in terms of speed and cost of collecting data for producing these indicators.
It represents the practical possibility of making available the indicator in question. It implies the feasibility of collecting the corresponding data by whatever means.