Respondents aged 16 and over who reported a longstanding illness or condition were asked ‘What is the matter with you?’ Details of the illness were recorded by the interviewer and coded during the interview using a computer-assisted coding frame. The results were later aggregated into groups which approximate to the chapter headings of the International Classification of Diseases (ICD9). Studies of the validity of self-reported data have shown that there is a high level of agreement between incidence based on self-reporting and on medical examinations, and between self-reporting and doctor diagnosis of specific conditions. The level of agreement is highest for those conditions which require ongoing treatment, have commonly recognised names and are salient to respondents because they cause discomfort or worry.

As in previous years of the GHS, the most common conditions reported by respondents were musculoskeletal problems and conditions of the heart and circulatory system. For most condition groups there was no statistically significant difference between men and women in the rate of reporting. The main exception was for musculoskeletal conditions, which was reported by 135 men and 161 women per 1000. There was no change from 1998 in the relative frequency of conditions.

For the majority of conditions a higher prevalence was found among older people compared with young people. The difference was more marked for some complaints than others.

• Whereas 68 per 1000 in the 16 to 44 age group reported a musculoskeletal condition, the corresponding rate among those aged 75 and over was 311 per 1000.
• A condition of the heart and circulatory system was reported at a rate of 17 per 1000 for those aged 16 to 44, compared with a rate of 308 per 1000 among people aged 75 and over.

The prevalence of mental disorders was greatest among those aged between 45 and 64. In this age group 36 per 1000 reported mental disorders in 2000, compared with the overall reporting rate of 27 per 1000. The GHS is based on a sample of private households and therefore has no data on people living in institutions. This may mean that the rates of mental disorders are an underestimate of the true population rates, particularly among those aged 75 and over.

Analysis by age and sex shows that, for all age groups above the age of 44, reported chronic respiratory problems were different for men and women. Among those aged 75 and over, men were twice as likely as women to report chronic respiratory problems (116 per 1000, compared with 58 per 1000). For the musculoskeletal system, within the younger age group (16 to 44) men were more likely than women to report a condition, at a rate of 77 per 1000 compared with 58 per 1000.

Table 7.15 shows the major disease groups separated into their component parts. This shows that the higher levels of women than men who reported musculoskeletal conditions in the older age groups was mainly explained by the proportion of women suffering from arthritis and rheumatism in the older age groups; 250 women out of 1000 aged 75 and over reported these conditions, compared with 131 men in the same age group.

• Bronchitis and emphysema was related to age, especially in men. There was almost no reporting among men aged 16-44, whereas 50 out of 1000 men aged 75 or over reported this condition.
• Hay fever was higher for young people, the rates out of 1000 were 8 for men aged 16-44, and 6 for women aged 16-44 whereas there were no reporting for those aged 75 or over.

Tables 7.16 and 7.17 look at the rate of reporting selected longstanding conditions by the socio-economic group of the household reference person. There was a clear pattern of higher prevalence of the conditions listed among those living in households where the household reference person was in a lower socio-economic group compared to a higher socio-economic group. For example, three times as many people in households headed by someone in an unskilled manual job, compared with a professional occupation, reported conditions which affected their musculoskeletal system (257 per 1000 compared with 83 per 1000). They were also more likely to report conditions in more than one group.