Age and Ageing (1975), 4, 152
REVIEWS AFTER ONE AND FIVE YEARS IN A LONGITUDINAL STUDY OF AGEING PERSONS J. S. MILNE AND J. M. CHOPIN Royal Victoria Hospital, Edinburgh
Summary A simple random sample of older people composed of 215 men and 272 women aged 62 years and over was examined in Edinburgh in 1968-9. After one year, 86 per cent of the men and 79 per cent of the women were re-examined; 7 per cent of the men and 4 per cent of the women had died and the remainder were not re-examined for various reasons, mainly refusal. After five years, 53 per cent of the men and 54 per cent of the women were re-examined; 36 per cent of the men and 22 per cent of the women had died and the remainder were not re-examined mainly because of various types of refusal. Causes of death resembled in frequency and sex differences those reported by the Registrar General. Methods used in tracing and improving cooperation of subjects are described. INTRODUCTION
A longitudinal study of ageing persons was begun in Edinburgh in January 1968. It consisted of examination by a physician, a psychiatrist and others. The physician used a semistructured questionnaire about physical health, a full clinical examination and a number of special examinations including anthropometry, audiometry, visual acuity, respiratory function tests, electrocardiography, haematology, biochemistry and radiographic measurements of heart size and bone mass. The psychiatrist used a semistructured questionnaire to perform a full psychiatric examination and carried out several standard tests of intellectual function. The reproducibility of questionnaires and measurements was tested before the study began. Reproducibility of measurements was tested after the original examination and before the reviews. The other investigators were a psychologist, a sociologist and a dietician. The present paper describes success, failure and death rates in examinations made one year and five years after the original examination and discusses these results and related factors. Differences between proportions were examined with the binomial theorem. O R I G I N A L EXAMINATION
This was made during 1968 and 1969. The sample was drawn from the population of persons born in 1905 or earlier who in January 1968 lived in an area composed of ten city wards in Edinburgh and who were on the list of a doctor with a surgery address in the defined area. A census made from Executive Council records listed 26 903 persons who qualified for inclusion in the population as defined. These people were on the lists of 91 doctors working in 50 general practices. Persons composing a simple random sample of 748 people drawn from the above population were approached through their general
Reviews After One and Five Years in a Longitudinal Study of Ageing Persons
153
practitioners to ask them to take part in the study. Those who accepted were examined. If the general practitioners reported refusal by any person, no further approach was made to that person. Of the 748 persons in the simple random sample, 487 were examined (65 per cent), 212 refused (28.5 per cent), 45 died after the survey began without being examined (6 per cent) and four (0.5 per cent) moved away after the survey began without being examined. The age and sex distributions of the 487 people who were examined are given in Table I. The method of sampling with a comparison of respondents and nonrespondents has been described in detail elsewhere (Milne et al., 1971). Table I. Age and sex distribution of persons in the original sample Age
Men
Women
62-69 70-79
122 73 20 215
137 101 34
Totals
272
These authors showed that age and sex distribution in the sample as drawn (748 people) did not differ significantly from the distributions in the 1966 Edinburgh sample census but the examined group (487 people) showed a significantly smaller proportion of women compared with that in the census. The age distributions within each sex in the examined group did not differ significantly from those in the 1966 census. The distribution of percentage acceptance rates at the original examination is given in Table II in respect of practices singlehanded or otherwise. The table shows that the mode for acceptance rate is in the 60-69 per cent group and that 30 of the 50 practices have acceptance rates between 50 per cent and 80 per cent. No difference emerges when acceptance rates in singlehanded practices are compared with those in practices with two or more doctors. Table II. Acceptance rates in general practices in the original examination of a longitudinal study of ageing persons Doctors in practice Percentage acceptance 1
2 1 1 4 5 3 1 1 5 23
_ 1 2 5 8 5 3 1 25
154
J. S. Milne and J. M. Chopin REVIEW AFTER O N E YEAR
One year after the first examination, the first review was arranged. No person in the study was contacted without first asking the general practitioner concerned whether a further approach was acceptable to the doctor or to the patient. Table III shows success and failure in the first review. The greater proportion of men (85.6 per cent) compared with women (78.7 per cent) who returned for examination is significant (P
REVIEWS AFTER ONE AND FIVE YEARS IN A LONGITUDINAL STUDY OF AGEING PERSONS J. S. MILNE AND J. M. CHOPIN Royal Victoria Hospital, Edinburgh
Summary A simple random sample of older people composed of 215 men and 272 women aged 62 years and over was examined in Edinburgh in 1968-9. After one year, 86 per cent of the men and 79 per cent of the women were re-examined; 7 per cent of the men and 4 per cent of the women had died and the remainder were not re-examined for various reasons, mainly refusal. After five years, 53 per cent of the men and 54 per cent of the women were re-examined; 36 per cent of the men and 22 per cent of the women had died and the remainder were not re-examined mainly because of various types of refusal. Causes of death resembled in frequency and sex differences those reported by the Registrar General. Methods used in tracing and improving cooperation of subjects are described. INTRODUCTION
A longitudinal study of ageing persons was begun in Edinburgh in January 1968. It consisted of examination by a physician, a psychiatrist and others. The physician used a semistructured questionnaire about physical health, a full clinical examination and a number of special examinations including anthropometry, audiometry, visual acuity, respiratory function tests, electrocardiography, haematology, biochemistry and radiographic measurements of heart size and bone mass. The psychiatrist used a semistructured questionnaire to perform a full psychiatric examination and carried out several standard tests of intellectual function. The reproducibility of questionnaires and measurements was tested before the study began. Reproducibility of measurements was tested after the original examination and before the reviews. The other investigators were a psychologist, a sociologist and a dietician. The present paper describes success, failure and death rates in examinations made one year and five years after the original examination and discusses these results and related factors. Differences between proportions were examined with the binomial theorem. O R I G I N A L EXAMINATION
This was made during 1968 and 1969. The sample was drawn from the population of persons born in 1905 or earlier who in January 1968 lived in an area composed of ten city wards in Edinburgh and who were on the list of a doctor with a surgery address in the defined area. A census made from Executive Council records listed 26 903 persons who qualified for inclusion in the population as defined. These people were on the lists of 91 doctors working in 50 general practices. Persons composing a simple random sample of 748 people drawn from the above population were approached through their general
Reviews After One and Five Years in a Longitudinal Study of Ageing Persons
153
practitioners to ask them to take part in the study. Those who accepted were examined. If the general practitioners reported refusal by any person, no further approach was made to that person. Of the 748 persons in the simple random sample, 487 were examined (65 per cent), 212 refused (28.5 per cent), 45 died after the survey began without being examined (6 per cent) and four (0.5 per cent) moved away after the survey began without being examined. The age and sex distributions of the 487 people who were examined are given in Table I. The method of sampling with a comparison of respondents and nonrespondents has been described in detail elsewhere (Milne et al., 1971). Table I. Age and sex distribution of persons in the original sample Age
Men
Women
62-69 70-79
122 73 20 215
137 101 34
Totals
272
These authors showed that age and sex distribution in the sample as drawn (748 people) did not differ significantly from the distributions in the 1966 Edinburgh sample census but the examined group (487 people) showed a significantly smaller proportion of women compared with that in the census. The age distributions within each sex in the examined group did not differ significantly from those in the 1966 census. The distribution of percentage acceptance rates at the original examination is given in Table II in respect of practices singlehanded or otherwise. The table shows that the mode for acceptance rate is in the 60-69 per cent group and that 30 of the 50 practices have acceptance rates between 50 per cent and 80 per cent. No difference emerges when acceptance rates in singlehanded practices are compared with those in practices with two or more doctors. Table II. Acceptance rates in general practices in the original examination of a longitudinal study of ageing persons Doctors in practice Percentage acceptance 1
2 1 1 4 5 3 1 1 5 23
_ 1 2 5 8 5 3 1 25
154
J. S. Milne and J. M. Chopin REVIEW AFTER O N E YEAR
One year after the first examination, the first review was arranged. No person in the study was contacted without first asking the general practitioner concerned whether a further approach was acceptable to the doctor or to the patient. Table III shows success and failure in the first review. The greater proportion of men (85.6 per cent) compared with women (78.7 per cent) who returned for examination is significant (P
