Martin J. Bass

Lack of impact of salt restriction advice on hypertensive patients

The response of known hypertensives to advice on sodium restriction was examined as part of a 5-year study on hypertension screening in family practice. The study comprised 34 family practices, pair-matched for location, activity level, and length of time in present practice. One practice in each matched pair was randomly allocated to an experimental or a control group. All hypertensive patients in each experimental practice were exposed to a management program which included dietary counseling to restrict sodium intake. A sample of hypertensive patients (N = 1,001) in both control and experimental groups was interviewed 3.5 years into the study. Although more subjects in experimental practices reported not adding salt (22.9%) compared with those in control practices (17.3%), the results of multivariate analysis showed that type of practice (experimental or control) was not significantly associated with salt use. Salt avoidance was strongly related to lower levels of education and to sex (men were less likely to use salt). Subjects who did not use salt also tended to avoid high-sodium foods. The response to nutritional advice was less favorable than expected. Difficulties in compliance with dietary recommendations are discussed.

Characteristics of highly rated family practice preceptors.

Student ratings of teaching, though controversial, demonstrate high reliability and acceptable validity. The study on which this article is based attempted to define the aspects of the family medicine preceptor and his practice which are significantly associated with the medical students assessment of the preceptors teaching ability. Questionnaires were sent to preceptors at the University of Western Ontario, and their responses were compared with student ratings by means of t-tests, correlation coefficients, and multiple regression. Higher teaching ability ratings were given to preceptors in group practice and nonurban practice and to those delegating more responsibility to students and using medication lists. Multiple-regression analyses using questionnaire data plus teaching ability subscores accounted for 88.1 percent of variance in student assessments of their clinical teachers. Suggestions for selection of preceptors are presented, together with proposals for further research into clinical teaching by family practice preceptors.

Sequential screening for hypertension in primary care

Abstract Plans are presented for the sequential screening of hypertension in primary care. The plans depend upon: (i) the number of stages k; (ii) the number of blood pressure readings per stage n; (iii) a threshold for true mean blood pressure gq1, above which pharmacological treatment is believed desirable; (iv) a threshold for true mean blood pressure gq0 below which pharmacological treatment is believed undesirable and (v) error probabilities associated with falsely classifying a person with mean blood pressure less than gq0. The plans are chosen to maximize the probability of correctly classifying a person with mean blood pressure greater than gq1.