Methodological issues of an epidemiological study: from the results of a study on psychological problems seen in outpatients visiting the internal medicine departments of general hospitals

Factors affecting disability in patients attending the internal medicine departments of general hospitals

The aim of this study was to investigate the effect of sociodemographic factors, physical factors and mental factors on the physical and social disability of patients attending outpatient clinics of general hospitals. Physical and psychiatric morbidity in 1580 consecutive patients attending the internal medicine department of general hospitals was assessed using a stratified two-stage sampling design method. Of the total, 336 patients completed the second stage interview composed of Primary Care Version of Composite International Diagnostic Interview and Groningen Social Disability Schedule to assess sociodemographic, physical and mental factors. In this study, restricted activity days, disability days and Brief Disability Questionnaire were used for the assessment of physical disability, and Groningen Social Disability Schedule was used for social disability. Sociodemographic, physical and mental factors were all related to disability. Among sociodemographic factors, unemployment was associated with physical disability and social disability mildly. Among physical factors, the severity of physical disease was not associated with disability and medically explained somatic symptoms were associated with disability. Furthermore, the mental factor was more strongly associated with physical and social disability. It could be said that the mental factor is more strongly associated with physical and social disability than sociodemographic or physical factors. In addition, even mild mental symptoms not leading to ICD-10 mental disorders affected disability. From the viewpoint of the patients' burden, it is important to assess the mental symptoms as well as physical status in outpatient clinics of internal medicine or primary care.