The problem in using simple tools e.g. chest symptoms for epidemiological surveys, designed to quantify the problem is that estimates from these simple surveys are considerable underestimates. Recent research has, however, paved the way for the use of these simpler tools for use in estimating tuberculosis case prevalence rates in the community. A tool which is simple, convenient to use and maintain, cheap but highly sensitive is called "screening tool". Such tools are used for making initial selection of the given population. Tuberculin test, X-ray & symptom elicitation are the main screening tools used for epidemiological surveys and TB Control Programme. In the programme, symptom elicitation and X-ray examination are the screening tools of choice for Case-finding. In the survey, tuberculin and X-ray are the only two tools used, although tuberculin is not a good screening tool (40% population infected). Use of symptom screening in surveys, however, is restricted in the absence of adequate information on comparison of prevalence rates obtained by this method of screening with the best estimate. The performance of symptom screening with either culture or smear microscopy have been attempted. They showed that by applying suitable correction factors they may be rendered comparable to the best estimate. The symptoms may be useful in the survey as a screening tool and may give the rates as proximate to the true rates as possible. They will enable considerable simplification of epidemiological studies in tuberculosis without compromising on the precision of the estimates arrived at.

Mass miniature radiography (MMR) is the usual tool for population screening in tuberculosis case prevalence surveys. However, this facility is not available at most centres in India. An attempt was made to study the feasibility of carrying out sputum positive case prevalence survey in a population by introducing methodological variation in the screening, in order to select those eligible for sputum test without resorting to the customary use of MMR for the purpose. The study was carried out in Bangalore rural district during 1984-1986. The area was the same as for six earlier prevalence surveys conducted since 1961. The population aged up to 44 years was tuberculin tested. Persons with test induration size of = 10 mm were eligible for sputum examination, besides all those aged over 45 years were eligible. It was observed that 78.4% of the registered population (29400) in the age group 10 years and above were required to undergo sputum examination by the present method of screening leading to a very high work load of sputum examination necessitating deployment of additional sputum cultures. Thus, the purpose of pre selection for sputum examination was hardly fulfilled. Further, a high contamination rate was observed. The changed screening procedure in this survey made comparison with the earlier data difficult.

The overall prevalence rate of cases was 438/100,000 in persons aged 10 years and above, while smear positive prevalence rate was 68/100,000. The observed prevalence rate was similar to earlier surveys, while smear positive prevalence rate was much lower. In conclusion, the screening methodology was found to be operationally unfeasible, ineffective and counterproductive to complicate the survey procedure in the quest for simplicity.

A study was conducted in 55 randomly selected villages of Nelamangala taluk, Bangalore district in 1975 (1) to estimate the prevalence of symptoms in the general population during the two months prior to the epidemiological survey, (2) to study the nature of action taken by these symptomatics and, (3) to find out through sputum examination as to how many of them suffer from pulmonary tuberculosis. The entire population was interviewed and sputum was collected from those aged five years and above having symptoms continuously for seven days and more. A coverage of 98.8% was obtained. Symptomatics among the directly interviewed were almost double (32.3%) of those who had to be interviewed by proxy (16.8%). Proportion of symptomatics were higher in the age groups twenty years and above. 24.8% were symptomatic during the reference period of two months and 16.7% had symptoms on the day of interview. ll.1% were found to have chest symptoms. The prevalence rate of tuberculosis was found to be 21 per 1000, (for males 28 and females 14). Cough was the most prevalent and the symptom of longest duration.

The findings suggest that symptoms questioning should focus more on cough and its combination with other symptoms. Symptoms questioning as a tool to detect cases has less potential than X-ray, but data reveal that leading questions can elicit more information on symptoms and action taking. The manner of action taking was the same for chest symptoms as for other symptoms and the proportion taking action is also the same for males and females. Government health facilities are found to be the most important source of relief, indigenous medicine having some importance marked second and the private practitioners ranking only third.

Persons suffering from pulmonary tuberculosis generally experience symptoms such as cough, chest pain, fever and haemoptysis. It is possible to identify the symptomatics by interviewing them during community health surveys. The symptom survey was carried out in 62 villages and 4 town blocks of Tumkur district in Karnataka as a sequel to an epidemiological survey undertaken to estimate the prevalence of tuberculosis. The data was collected through structured schedule. The interviewers were given the identification details of individuals having X-ray shadows suggestive of tuberculosis and an equal number of matched controls within 4 weeks of the survey. A total of 1752 persons were taken into the study of whom 875 had x ray shadows and 877 were normals. Of the total persons under study 89.7% were satisfactorily interviewed. It was observed that 42.6% of the total symptomatics gave history of one symptom at the first general question, 13% responded having symptoms after being asked specific questions. In conclusion a 42.6% affirmative response to the initial question of 'How is your health' is noteworthy that an investigator is acceptable health agency as the interviewee is willing to confide in him regarding his health problems. Additional number of persons responded to direct specific questions.

It must be pointed out that interview is a generic term applied to a tool that may be used for obtaining information through verbal communication. As a tool in surveys for screening for tuberculosis it is amenable to divese techniques and has great potentialities of being applied to different situations and various categories of respondents. Hence, it is necessary to identify the nature of data to be obtained and to decide on the technique that would be most suitable. Proper training, skill and supervision of the interviewer can obviate any possible bias and subjectivity that could vitiate an interview. As compared to many of the tools of social science research, the interview is simple, easy and amenable to being used in live situations. It is also of prime importance among populations for whom vocalisation is the most important medium of communication. Hence, in a community survey for the estimation of the prevalence of chest symptomatics the interview can be a valuable tool. It also shows that the interview is adequate as a tool of community survey in tuberculosis.

A study on awareness of symptoms of pulmonary tuberculosis and action taking was repeated in the 62 villages and 4 town blocks of Tumkur district of Karnataka after an interval of 12 years. In the earlier study, 2106 persons formed the study population. In the present study, 1752 were intaken to obtain a comparison of these 1752 intaken persons who were eligible for interview, 875 were X-ray positive and 877 X-ray normal (matched control).

The study showed that 95% of patients having radiologically active tuberculosis by both X-ray readers, 70% by one reader, 49.5% inactive by both readers, were aware of symptoms. According to the bacteriological status 79.5% had symptoms among those who were sputum positive by both microscopy and culture, 62.2% among those positive by culture alone and 73.7% among patients sputum positive by any method. Regarding action taking it was observed that 49.5% of the bacteriologically positive patients took some action compared by 70% of those found to have radiologically active disease by both X-ray readers. Thus action taking was higher among the latter category in both the studies. It may be due to the fact that extent of lesions are less advanced among those bacteriologically positive than among those who were in radiologically positive stage.

The findings of the study are similar to the earlier awareness study carried out in 1963 in the same area (Tumkur). This also indicates that in spite of having advantage of DTP for a decade actual and total benefits have not reached the people.

This study based on an individualistic model examines the significance of factors such as symptom awareness, knowledge about the disease, recall of clinic instructions, economic problems and social interaction in the treatment regularity of patients with pulmonary tuberculosis through a multi dimensional comparison of regular patients, irregular patients and their households. There was no difference in the symptom awareness of the two groups of patients. Thus frequency of medical visits is to adopt the sick role than of stress. In NTP patients are denied the sick role has “rest” and “special diet” the vital elements of traditional treatment are not recommended as part of treatment. Yet, three of the four cardinal symptoms of pulmonary tuberculosis, cough fever and haemoptysis being of a nature observable by others, have been observed by the households to the extent similar to patients awareness. Most of the patients who take treatment from non- paying centres such as the LWTDTC live in overcrowded areas where there is generally a high degree of neighbourhood interaction not only social but in sharing common utilities such as courtyard, water tap, bath room, toilet etc. It is therefore not surprising that nearly half of the patients and households said that the neighbours knew about the patient's illness.

Seeking multiple sources of treatment is a common behaviour pattern of patients. Yet, it is disconcerting to find that tuberculosis patients who can ill afford to pay and who need to be under treatment for a long period should 'shop around' for treatment. It is the irregular patients who have sought treatment at other agencies more often. The study shows that patients showing regular drug collection have had help from household members in collecting the drugs. They have also had help from household members in remembering to consume the drugs. More of the households of the regulars mentioned LWTDTC as the place of treatment while in the in case of the households of the irregulars mentioned several places of treatment.

No significant differences were seen between the regular and irregular patients in their social interactions within the households or in the behaviour of households towards the patients. To the household, economic difficulties were the most important, perhaps for the reason that the patients were men in the working age group. Though economic difficulties were important to patients also the predominant aspect was pain and discomfort the physical dimensions of suffering. A treatment agency that can pay adequate attention to the relief of physical suffering and non- relapse of symptoms can perhaps help to improve treatment regularity of tuberculosis patients appreciably.

This study was undertaken in 34 villages and 4 town blocks where a few weeks earlier an epidemiological survey was carried out. All persons above 20 years whose photofluorograms were read as inactive, probably active, or active by at least one reader, were age sex matched with an equal number of X-ray normals, to form the experimental and control groups respectively. Thus, a total of 2,106 were eligible for social investigation. Interview sheets, with particulars of the name and location of village, household number, and individual number and the identifiable data of the interviewees were made available to the social investigators at random for contacting and interviewing them at their homes. The interviews were non- suggestive in nature and deep probing on the details of symptoms experienced by the respondent, which were fully recorded. About 79% of the experimental group and 83% of the control group were satisfactorily interviewed, which constituted the data further analysed. Of the numerous symptoms recorded, only that were associated with pulmonary tuberculosis were considered, of which cough occurring for one month or more, fever for a month or more, pain in the chest, haemoptysis and all combination of these four symptoms were analysed statistically.

Cough was found to be the most important single symptom. It was not only the most frequent symptom alone or in combination in the experimental group but was less frequent in the control group that 69% of sputum positive and 46% of radiological positive had cough while only 9% of the control group had it. Considerably fewer people had fever and pain in the chest. Pain in the chest appears to be non- specific, giving a ratio of only 2:l among the experimental and control groups while fever was in the ratio of 6:l and haemoptysis was ll:l. It was seen that 69% of the sputum positive cases, 52% of the X-ray active or probably active, 29% of the inactive and 15% of the normals (control group) had at least one of the above mentioned symptoms. In all the groups, the proportion of symptoms were higher among males than among females. In both males and females the prevalence of symptoms was higher in the middle age groups than among the younger or older groups. This age variation was more marked in the females. The findings of the study were analysed further along with the data obtained from a couple of minor investigations, conducted in the rest of the 28 villages which formed the total of the villages surveyed epidemiologically. This brought out further that 95% of bacteriologically positive cases are aware of symptoms, 72% experience 'worry awareness' and 52% form the action taking group. The above findings have been of considerable importance in planning further studies and in formulating the National Tuberculosis Programme.

Case-finding and treatment activities in the National Tuberculosis Programme (NTP) are mainly dependent on self reporting chest symptomatics. It was of main interest to find out that patients who report to the health institutions due to suffering remain symptom free later on or there is a recurrence of symptoms among sputum positive patients during 14 intervening years i.e., from 1961-1974. The follow up was carried out in 1974, in spite of such a long interval, information from 20.3% of the patients including dead was collected.

At the time of diagnosis in 1961 at LWC, 91.6% of patients had symptoms. During the total period from 1961 to the time of interview 7-16% had recurrence during each of the intervening years. Recall was possible because majority of them have taken action. But at the time of interview 29.7% reported to be having symptoms, of them nearly half had symptoms for more than 6 months. It is likely that during preceding years also there might have been a higher percentage of symptoms but the recall was poor. Considering the total duration of symptoms, 52% had experienced symptoms for more than 6 months.