Expected Treatment Effect Research Articles

Impact of behavior management programs on exercise adherence.

Intervention: Behavior Management Outcome: Exercise Adherence Impact of Intervention on Outcome: Dropout from exercise programs in most settings averages 50% in the first 6 months? Interventions using a variety of behaviormanagement techniques have been successful in improving short-term adherence to exercise. Adherence rates as high as 97% have been reported2; however, data on long-term maintenance of exercise habits newly acquired during these interventions are currently not available. Evidence Rating: 2 (Acceptable) Best Supportive Research: Table 1 describes five studies that lasted a minimum of 3 months and included a quantifiable measure of adherence, a measure of physical fitness improvement to corroborate reported physical activity, and a reasonable number of study participants. Where appropriate, the size of the expected treatment effect, expressed as the binomial effect size (BES) has been included? Research Agenda Questions Addressed: #3: To what extent do changes in behaviors, health signs, and symptoms occur after health promotion programs are provided? Are the changes correlational or causal? #7: What are the characteristics of health promotion programs that produce the behaviors, health signs, and symptoms that produce positive outcomes? Current State of the Science: Typically, 50% of the individuals who begin an exercise program stop within the first 6 months? Research suggests similar patterns of dropout in a wide variety of settings with diverse popula-

Ambulatory 24-Hour Blood Pressure Versus Self-Measured Blood Pressure in Pharmacologic Trials

In recent years, indirect ambulatory 24-h blood pressure monitoring and self-measurement at home have gained increasing importance in pharmacologic studies. Both methods have important advantages over conventional casual blood pressure determinations in the clinic. The better reproducibility of blood pressure recordings by either ambulatory monitoring or home readings suggests that both techniques are superior to office readings for evaluating the effect of antihypertensive therapy. The multiple readings obtained during ambulatory 24-h monitoring or by self-measurement at home reduce the variability of blood pressure estimates and substantially decrease the number of patients needed to detect clinically relevant blood pressure differences. Furthermore, dose-response relationships of new and established antihypertensive drugs are improved, as the random effect of blood pressure measurements falls below the expected treatment effect. Although there is some overlap between the information obtained with home and ambulatory monitoring, there are also important differences. Ambulatory monitoring provides information about the diurnal profile of blood pressure and has great advantages for trials investigating the time course of a particular drug. Self-measurement can provide repeated measurements in the same situation over prolonged periods of time, and therefore is ideally suited for monitoring changes in blood pressure induced by treatment or progression of the disease. In pharmacologic studies both techniques are thus complementary.

Sex therapy outcome research: a reappraisal of methodology. 1. A treatment study of male sexual dysfunction.

In the first section a controlled treatment study of male sexual dysfunction is described. 'Unlucky' randomization of subjects yielded treatment groups which differed with respect to variables of possible prognostic significance. Hence the results are largely uninterpretable. In the second section the predominantly negative or inconsistent findings in sex therapy outcome research are reviewed and methodological problems, such as those described in the first part, are considered as possible reasons for these negative findings. The interrelationships are explored between small treatment groups, prognostic variability, bias, power, and small expected treatment effects. A strategy for future research is proposed, with particular emphasis on the recognition and use of relevant prognostic indices.

The use of a liver biopsy technique for investigating the effects of hexachlorobenzene on some drug-metabolising enzymes in sheep

Several parameters of drug-metabolising capacity were measured in samples taken from various regions of the sheep liver. A statistically significant difference of 10 per cent between mean values of enzyme activities of the ventral and dorsal lobes was found. This could be ignored when compared with the expected treatment effect. It is concluded that the biopsy technique provides a sufficiently representative sample of the whole liver for use in studies of the type described. The results also indicated that the liver enzyme levels of young lambs were lower than those of older lambs and adult sheep. Sheep dosed with hexachlorobenzene (hcb) showed increased activities of aniline hydroxylase and 4-nitroanisole O-demethylase but not of the NADPH-independent esterases. It is concluded that HCB induces the drug-metabolising enzymes of sheep liver.