The H.I.P. study of incidence and prognosis of coronary heart disease: Methodology

Experience during the past two years indicates that the prepaid medical care setting of H.I.P. provides a practical way of conducting a large scale study of the incidence and prognosis of manifestations of CHD newly diagnosed in a defined population of 120,000 adults.

Abstract

Experience during the past two years indicates that the prepaid medical care setting of H.I.P. provides a practical way of conducting a large scale study of the incidence and prognosis of manifestations of CHD newly diagnosed in a defined population of 120,000 adults. Characteristics of this population are established by mail surveys. The records developed in the normal course of medical care in H.I.P. are used as the initial screening mechanism for identifying those individuals who may have incurred a new manifestation of CHD. Detailed historical, physical, and ECG data are obtained at examinations conducted by a study staff of specially trained internists utilizing standardized methods and highly structured reporting forms. Structured non-medical interviews are carried out at these sessions by trained study staff workers. These data are supplemented by information abstracted from hospital and medical records. The final diagnostic classification is made by the study medical director in accord with criteria developed specifically for this purpose. Individuals satisfying the study criteria for a newly diagnosed manifestation of CHD are followed at regular intervals to define the prognosis of that manifestation, and to relate the course to a number of medical, physiologic, demographic, social, and personal characteristics. The mechanism described is highly efficient for identifying and classifying large numbers of patients soon after the earliest medical suspicion of a variety of manifestations of CHD, and is particularly suited to a study with primary emphasis on the prognosis of CHD from the time of initial diagnosis.