Entry to a health centre: conduct and outcome of a prospective study

The article describes a prospective study into the effect that moving to a health centre had on a doctor's activities in certain areas of care: type of consultation, diagnostic instruments used, laboratory tests, prescriptions, psychotherapeutic content and referrals to specialists. It indicates how the design of the study had to be modified while it was in progress, in response to circumstances which could not be anticipated while it was being planned. The lessons learned from the experience are reported. The study showed that health centre entry was associated with less home visiting; none of the other activities under investigation were affected. However, if a 'control' had not been incorporated into the study, different and mistaken conclusions might have been drawn. It is argued that since developments in service practice can excite extreme supportive or critical comment based on inadequate evidence, there is a need for prospective controlled studies of this type, if the provision of general medical care is to have scientific credibility.