Overview of the Activity Counseling Trial (ACT) intervention for promoting physical activity in primary health care settings. Activity Counseling Trial Research Group

Counseling by health care providers has the potential to increase physical activity in sedentary patients, yet few studies have tested interventions for physical activity counseling delivered in health care settings. The Activity Counseling Trial (ACT) is a 5-yr randomized clinical trial to evaluate the efficacy of two primary care, practice-based physical activity behavioral interventions relative to a standard care control condition. A total of 874 sedentary men and women, 35-75 yr of age, have been recruited from primary care physician offices at three clinical centers for 2 yr of participation. They were randomly assigned to one of three experimental conditions that vary, in a hierarchical fashion, by level of counseling intensity and resource requirements. The interventions, which are based on social cognitive theory and the transtheoretical model, are designed to alter empirically based psychosocial mediators that are known to be associated with physical activity. The present paper describes the theoretical background of the intervention, the intervention methods, and intervention training and quality control procedures.     

Rapid early action for coronary treatment: rationale, design, and baseline characteristics. REACT Research Group

OBJECTIVE: Early reperfusion for acute myocardial infarction (AMI) can reduce morbidity and mortality, yet there is often delay in accessing medical care after symptom onset. This report describes the design and baseline characteristics of the Rapid Early Action for Coronary Treatment (REACT) community trial, which is testing community intervention to reduce delay. METHODS: Twenty U.S. communities were pair-matched and randomly assigned within pairs to intervention or comparison. Four months of baseline data collection was followed by an 18-month intervention of community organization and public, patient, and health professional education. Primary cases were community residents seen in the ED with chest pain, admitted with suspected acute cardiac ischemia, and discharged with a diagnosis related to coronary heart disease. The primary outcome was delay time from symptom onset to ED arrival. Secondary outcomes included delay time in patients with MI/unstable angina, hospital case-fatality rate and length of stay, receipt of reperfusion, and ED/emergency medical services utilization. Impact on public and patient knowledge, attitudes, and intentions was measured by telephone interviews. Characteristics of communities and cases and comparability of paired communities at baseline were assessed. RESULTS: Baseline cases are 46% female, 14% minorities, and 73% aged > or =55 years, and paired communities have similar demographics characteristics. Median delay time (available for 72% of cases) is 2.3 hours and does not vary between treatment conditions (p > 0.86). CONCLUSIONS: REACT communities approximate the demographic distribution of the United States and there is baseline comparability between the intervention and comparison groups. The REACT trial will provide valuable information for community educational programs to reduce patient delay for AMI symptoms.     

The Sleep Heart Health Study: design, rationale, and methods

The Sleep Heart Health Study (SHHS) is a prospective cohort study designed to investigate obstructive sleep apnea (OSA) and other sleep-disordered breathing (SDB) as risk factors for the development of cardiovascular disease. The study is designed to enroll 6,600 adult participants aged 40 years and older who will undergo a home polysomnogram to assess the presence of OSA and other SDB. Participants in SHHS have been recruited from cohort studies in progress. Therefore, SHHS adds the assessment of OSA to the protocols of these studies and will use already collected data on the principal risk factors for cardiovascular disease as well as follow-up and outcome information pertaining to cardiovascular disease. Parent cohort studies and recruitment targets for these cohorts are the following: Atherosclerosis Risk in Communities Study (1,750 participants), Cardiovascular Health Study (1,350 participants), Framingham Heart Study (1,000 participants), Strong Heart Study (600 participants), New York Hypertension Cohorts (1,000 participants), and Tucson Epidemiologic Study of Airways Obstructive Diseases and the Health and Environment Study (900 participants). As part of the parent study follow-up procedures, participants will be surveyed at periodic intervals for the incidence and recurrence of cardiovascular disease events. The study provides sufficient statistical power for assessing OSA and other SDB as risk factors for major cardiovascular events, including myocardial infarction and stroke.     

Perceived environmental predictors of physical activity over 6 months in adults: Activity Counseling Trial.

[Correction Notice: An erratum for this article was reported in Vol 27(2) of Health Psychology (see record 2008-12766-001). One result in Table 2 was misinterpreted in the text. It was reported that men who responded "yes" to frequently seeing people being active in their neighborhoods did about 75 minutes more physical activity per week (pPurpose: In the present study, the authors extend previous cross-sectional findings by using a prospective design to determine whether physical and social environmental characteristics predict physical activity over 6 months. Design: Inactive adults were recruited to the Activity Counseling Trial, a multicenter, randomized, controlled trial of physical activity intervention in primary care. Participants were 387 women and 474 men aged 35-75 years in 3 regions; 1/3 were minorities; 56% had some college education. Baseline perceived environmental variables were used to predict physical activity at 6 months, adjusting for experimental condition and other potential moderators. Measures: The validated 7-day physical activity recall interview was used to estimate minutes of moderate to vigorous physical activity. A standardized survey was used to measure social and physical environmental variables around the home and neighborhood. Results: Women reporting no unattended dogs and low crime in their neighborhoods and men reporting frequently seeing people being active in their neighborhoods did 50-75 more minutes of physical activity per week than did those with different environmental characteristics. Interactions of environmental variables with age group suggested that older adults may be more affected by environmental variables than are younger adults. Conclusions: Self-reported social and physical environmental variables were significantly related to moderate to vigorous physical activity among a diverse sample of adults living in 3 regions of the United States. These prospective findings strengthen the conclusion from previous cross-sectional studies that environmental variables are important correlates of physical activity. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Development and testing of a seven-day dietary recall. Dietary Assessment Working Group of the Worcester Area Trial for Counseling in Hyperlipidemia (WATCH)

Using multiple 24-hr recalls (24HR) we tested the Seven Day Dietary Recall (7DDR) developed to assess nutrient exposures, especially lipids, in dietary interventions and other clinical trials requiring measurement of effect over moderate time periods. A total of 261 individuals in three studies completed a 7DDR at the end of a 3- to 5-week period during which 3 to 7 24HR were telephone-administered on randomly selected days. One of these studies and data from one additional study (total n = 678) allowed us to test the ability of the 7DDR to predict serum lipid changes in an intervention setting. In correlation and linear regression analyses, high levels of agreement between 7DDR and 24HR were obtained. For total energy: r = 0.67 and b = 0.69, and for total fat intake (g/day): r = 0.67 and b = 0.80. When 7 days of 24HR were available agreement tended to be higher. For total energy: r = 0.69 and b = 0.95, and for total fat (g/day): r = 0.71 and b = 1.04. Data derived from the 7DDR and fit to the Keys and Hegsted equations closely predicted actual changes in total serum cholesterol (within 15% and 10%, respectively). The 7DDR is a relatively easily administered, sensitive method to assess short-term changes in dietary fat consumption in individuals.     

The Dutch Renal Artery Stenosis Intervention Cooperative (DRASTIC) Study: rationale, design and inclusion data

RATIONALE: Renal artery stenosis may lead to renovascular hypertension, risking multiple organ damage including damage to the contralateral kidney. Progression of stenosis may impair the function of the affected kidney. It is important to identify individuals with this disease among hypertensive patients. The first aim of the Dutch Renal Artery Stenosis Intervention Cooperative (DRASTIC) study is to assess the prevalence of renal artery stenosis in patients with well-defined forms of drug-resistant hypertension, and to determine the predictive value of clinical characteristics and diagnostic tests in these pre-selected patients. With regard to treatment, the effect of renal angioplasty on hypertension is disappointing in atherosclerotic stenosis and technical failure frequently occurs. Therefore, the second aim is to compare the effects of balloon angioplasty and antihypertensive medication on blood pressure in patients with atherosclerotic renal artery stenosis. DESIGN HYPERTENSIVE: patients receiving standard antihypertensive medication in whom diastolic blood pressure remained > or =95 mmHg during three consecutive visits to the outpatient clinic underwent full diagnostic work-up, including renal arteriography. The prevalence of renal artery stenosis in this well-defined patient group was then established, and the predictive value of the various diagnostic tests was assessed. Patients with an atherosclerotic renal artery stenosis of > or =50% were then randomly assigned to balloon angioplasty or to treatment with antihypertensive drugs. After 1 year of intensive follow-up of blood pressure and renal function, re-arteriography was performed. CONCLUSION: In total, 1205 patients have been included in the study, about 500 have received diagnostic work-up, and it is expected that 100 patients will be randomly assigned for renal angioplasty or medical treatment.     

A secondary prevention trial of antioxidant vitamins and cardiovascular disease in women. Rationale, design, and methods. The WACS Research Group

The evidence for a potential benefit of antioxidant vitamins in the prevention and therapy of atherosclerotic disease is derived from laboratory, clinical, and observational epidemiologic studies but remains inconclusive. Data from randomized clinical trials are sparse, particularly for women. Therefore, it is both timely and important to conduct large-scale primary and secondary prevention trials of antioxidants and cardiovascular disease (CVD). The Women's Antioxidant and Cardiovascular Study (WACS) is a randomized, double-blind, placebo-controlled secondary prevention trial of the balance of benefits and risks of antioxidant vitamins (vitamins E and C, and beta-carotene) among 8000 women with preexisting CVD. This secondary prevention trial will be conducted as a companion to the recently started Women's Health Study, a primary prevention trial of vitamin E and beta-carotene, as well as aspirin. In the WACS, US female health professionals aged 40 years and older with a history of myocardial infarction, angina pectoris, coronary revascularization, stroke, transient cerebral ischemia, carotid endarterectomy, or peripheral artery surgery will be randomly assigned, utilizing a 2 x 2 x 2 factorial design, to receive vitamin E, vitamin C, beta-carotene, and/or placebo. Cardiovascular end points include nonfatal myocardial infarction, nonfatal stroke, coronary revascularization procedures, and total CVD mortality. The present article describes the rationale, design, and methods of the trial.     

Perceived environmental predictors of physical activity over 6 months in adults: Activity Counseling Trial: Correction to Sallis et al. (2007).

Reports an error in Perceived environmental predictors of physical activity over 6 months in adults: Activity Counseling Trial by James F. Sallis, Abby C. King, John R. Sirard and Cheryl L. Albright (Health Psychology, 2007[Nov], Vol 26[6], 701-709). One result in Table 2 was misinterpreted in the text. It was reported that men who responded yes to frequently seeing people being active in their neighborhoods did about 75 minutes more physical activity per week (p2007-16656-008.) Purpose: In the present study, the authors extend previous cross-sectional findings by using a prospective design to determine whether physical and social environmental characteristics predict physical activity over 6 months. Design: Inactive adults were recruited to the Activity Counseling Trial, a multicenter, randomized, controlled trial of physical activity intervention in primary care. Participants were 387 women and 474 men aged 35-75 years in 3 regions; 1/3 were minorities; 56% had some college education. Baseline perceived environmental variables were used to predict physical activity at 6 months, adjusting for experimental condition and other potential moderators. Measures: The validated 7-day physical activity recall interview was used to estimate minutes of moderate to vigorous physical activity. A standardized survey was used to measure social and physical environmental variables around the home and neighborhood. Results: Women reporting no unattended dogs and low crime in their neighborhoods and men reporting frequently seeing people being active in their neighborhoods did 50-75 more minutes of physical activity per week than did those with different environmental characteristics. Interactions of environmental variables with age group suggested that older adults may be more affected by environmental variables than are younger adults. Conclusions: Self-reported social and physical environmental variables were significantly related to moderate to vigorous physical activity among a diverse sample of adults living in 3 regions of the United States. These prospective findings strengthen the conclusion from previous cross-sectional studies that environmental variables are important correlates of physical activity. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Narratology, Cultural Psychology, and Counseling Research.

Narratological research is defined in relation to narrative theory and a cultural psychology perspective. Narrative concepts and methodology are explained, including the configural mode of understanding and principles of narrative analysis. Examples of application in psychological and counseling research are presented, with a discussion of issues of validity and voice. Suggestions are made on how narrative studies are to be evaluated. It is concluded that narratological research, with its focus on meanings and the storied nature of human life, can be especially useful in discovery research on identity development and the experience of counseling and life transitions. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

The Study of Health Assessment and Risk in Ethnic groups (SHARE): rationale and design. The SHARE Investigators

The Study of Health Assessment and Risk in Ethnic groups (SHARE) is a study to determine the risk factors for atherosclerosis among three ethnic populations in Canada. Three hundred and thirty South Asian Canadian, 320 Chinese Canadian and 320 European Canadian men and women between 35 and 75 years of age are being randomly sampled from communities in Hamilton and Toronto, Ontario and Edmonton, Alberta for assessment of conventional (i.e., smoking, dyslipidemia, diabetes and hypertension) and emerging (i.e., candidate genes for atherosclerosis, homocysteine, fibrinolytic parameters, neurohormones, glucose intolerance, markers of infection, socioeconomic status, psychosocial status and diet) cardiovascular disease risk factors. Subclinical atherosclerosis is measured by quantitative B-mode ultrasonography of the carotid arteries, and other objective measures of vascular disease are a 12-lead electrocardiogram, a two-dimensional echocardiogram, ankle to arm blood pressure ratio and urine microalbumin concentration. The relationship between the conventional and emerging risk factors, and atherosclerosis, vascular disease and markers of end-organ damage will be evaluated between and within ethnic groups.     

Heart and Estrogen/progestin Replacement Study (HERS): design, methods, and baseline characteristics

The Heart and Estrogen/progestin Replacement Study (HERS) is a randomized, double-blind, placebo-controlled trial designed to test the efficacy and safety of estrogen plus progestin therapy for prevention of recurrent coronary heart disease (CHD) events in women. The participants are postmenopausal women with a uterus and with CHD as evidenced by prior myocardial infarction, coronary artery bypass graft surgery, percutaneous transluminal coronary angioplasty, or other mechanical revascularization or at least 50% occlusion of a major coronary artery. Between February 1993 and September 1994, 20 HERS centers recruited and randomized 2763 women. Participants ranged in age from 44 to 79 years, with a mean age of 66.7 (SD 6.7) years. Most participants were white (89%), married (57%), and had completed high school or some college (80%). As expected, the prevalence of coronary risk factors was high: 62% were past or current smokers, 59% had hypertension, 90% had serum LDL-cholesterol of 100 mg/dL or higher, and 23% had diabetes. Each woman was randomly assigned to receive one tablet containing 0.625 mg conjugated estrogens plus 2.5 mg medroxyprogesterone acetate daily or an identical placebo. Participants will be evaluated every 4 months for an average of 4.2 years for the occurrence of CHD events (CHD death and nonfatal myocardial infarction). We will also assess other major CHD endpoints, including revascularization and hospitalization for unstable angina. The primary analysis will compare the rate of CHD events in women assigned to active treatment with the rate in those assigned to placebo. The trial was designed to have power greater than 90% to detect a 35% reduction in the incidence of CHD events, assuming a 50% lag in effect for 2 years and a 5% annual event rate in the placebo group. The design, analysis, and conduct of the study are controlled by the Steering Committee of Principal Investigators and coordinated at the University of California, San Francisco. HERS is the largest trial of any intervention to reduce the risk of recurrent CHD events in women with heart disease and is the first controlled trial to seek evidence of the efficacy and safety of postmenopausal hormone therapy to prevent recurrent CHD events.     

Fibrin sealant: scientific rationale, production methods, properties, and current clinical use

Morphological analysis of the brains from 100 cases of full blown AIDS patients observed in the course of 1987-1995 years was performed. The material comprised 96 males, 3 females and 1 infant, 11 months old. Early material consisted almost exclusively of homo- and bisexuals, while in the last years heterosexual drug addicts prevailed. Gross brain examination revealed focal changes in 25% of cases, most of them being connected either with opportunistic infections or primary proliferating malignancies. Brain atrophy with an evident regional differences was observed macroscopically in 35 cases. Microscopic examination allowed detection of pathological changes in the brains of 87 cases, although in the remaining 13 cases there occurred some slight abnormalities taking the form of non-specific neuronal degeneration and loss, considered as resulting from perimortal cardio-pulmonary insufficiency or bleeding. Specific HIV-related changes in the form of HIV-encephalitis, HIV-encephalopathy or coexistence of both and HIV-leptomeningitis as well as HIV-vasculitis were present in 35 cases. They were accompanied by HIV-associated changes (vacuolar myelopathy, vacuolar leukoencephalopathy and selective poliodystrophy). Very seldom they appeared as independent pathological features and were characterized by very low frequency. Opportunistic infections composed the largest group of 59 cases. Proliferative malignancies occurred altogether in eleven cases, 10 of which were primary and secondary brain lymphomas. One case of Kaposi sarcoma completed the neoplastic series. Sixteen cases revealed various types of brain pathology such as hepatogenic encephalopathy, traumatic cortical scars, central pontine myelinolysis etc. The 59 cases of opportunistic infections consisted of a wide spectrum of viral and bacterial as well as fungal and protozoan infections. Among viral infections cytomegalovirus encephalitis was the most common, way ahead the progressive multifocal leukoencephalopathy. The second in frequency among opportunistic infections was brain toxoplasmosis and some fungal infections such as cryptococcosis and aspergillosis. Bacterial infections were in fact limited to tuberculosis, taking the form of granulomatous leptomeningitis with severe vascular pathology and/or tuberculoma formation. Many pathological processes appearing in a single case was characteristic feature of our collection. There was coexistence of HIV-specific CNS pathology and opportunistic infections, malignant neoplastic growth and other types of pathology. Various opportunistic infections coexisted without HIV-specific changes as well as malignant proliferation with opportunistic infections. Similarities and differences of our series were compared with data characterizing other, earlier collections of NeuroAIDS.     

Paradigms, Praxis, Problems, and Promise: Grounded Theory in Counseling Psychology Research.

In this article, the author presents an overview of the qualitative research approach termed grounded theory (B. G. Glaser, 1978, 1992; B. G. Glaser & A. L. Strauss, 1967; A. L. Strauss, 1987; A. L. Strauss & J. Corbin, 1990, 1998). The author first locates the method conceptually and paradigmatically (paradigms) and then outlines the procedures for implementing it and judging its quality (praxis). The author follows with a discussion of selected issues that arise in using the approach (problems) and concludes by noting the appropriateness of grounded theory for counseling psychology research (promise). (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Texas Medication Algorithm Project: definitions, rationale, and methods to develop medication algorithms

BACKGROUND: The Texas Medication Algorithm Project (TMAP), a public-academic collaborative effort, is a 3-phase project to develop, implement, and evaluate medication treatment algorithms for public sector patients with schizophrenia, major depressive disorders, or bipolar disorders. DISCUSSION: This paper, the first in a series describing the activities of the TMAP, focuses on the various definitions and reasons why guidelines have gained popularity. Also discussed are their strengths, the limitations of the various methods used to develop them, and potential barriers to their implementation.     

The polyp prevention trial I: rationale, design, recruitment, and baseline participant characteristics

The Polyp Prevention Trial (PPT) is a multicenter randomized controlled trial examining the effect of a low-fat (20% of total energy intake), high-fiber (18 g/1000 kcal), high-vegetable and -fruit (5-8 daily servings) dietary pattern on the recurrence of adenomatous polyps of the large bowel, precursors of most colorectal malignancies. Eligibility criteria include one or more adenomas removed within 6 months of randomization; complete nonsurgical polyp removal and complete colonic examination to the cecum at the qualifying colonoscopy: age 35 years of more; no history of colorectal cancer, inflammatory bowel disease, or large bowel resection; and satisfactory completion of a food frequency questionnaire and 4-day food record. Of approximately 38,277 potential participants with one or more polyps recently resected, investigators at eight clinical centers randomized 2,079 (5.4%; 1,037 in the intervention and 1,042 in the control arm) between June 1991 and January 1994, making the PPT the largest adenoma recurrence trial ever conducted. Of PPT participants, 35% are women and 10% are minorities. At study entry, participants averaged 61.4 years of age; 14% of them smoked, and 22% used aspirin. At the baseline colonoscopy, 35% of participants had two or more adenomas, and 29% had at least one large (> of = 1 cm) adenoma. Demographic, behavioral, dietary, and clinical characteristics are comparable across the two study arms. Participants have repeat colonoscopies after 1 (T(1)) and 4 (T(4)) years of follow-up. The primary end point is adenoma recurrence; secondary end points include number, size, location, and histology of adenomas. All resected lesions are reviewed centrally by gastrointestinal pathologists. The trial provides 90% power to detect a reduction of 24% in the annual adenoma recurrence rate. The primary analytic period, on which sample size calculations were based is 3 years (T(1) to T(4)), which permits a 1-year lag time for the intervention to work and allows a more definitive clearing of lesions at T(1), given that at least 10-15% of polyps may be missed at baseline. The final (T(4)) colonoscopies are expected to be completed in early 1998.     

The Lesbian, Gay and Bisexual Affirmative Counseling Self-Efficacy Inventory (LGB-CSI): Development, validation, and training implications.

Five studies on the development of the Lesbian, Gay, and Bisexual Affirmative Counseling Self-Efficacy Inventory (LGB-CSI) were conducted. Exploratory and confirmatory factor analyses of an initial pool of 64 items yielded 5 factors that assess counselor self-efficacy to perform lesbian, gay, and bisexual (LGB) affirmative counseling behaviors (Application of Knowledge, Advocacy Skills, Self-Awareness, Relationship, and Assessment Skills). The LGB-CSI evidenced high internal consistency; however, low test-retest reliability was found over a 2-week period. Convergent validity was supported by correlations with measures of general counseling self-efficacy and attitudes toward LGB individuals. Discriminant validity was evidenced by an absence of relations between the LGB-CSI and measures of social desirability, self-deceptive positivity, and impression management. Construct validity was supported by findings indicating varying levels of self-efficacy commensurate with status in the field. Recommendations for training interventions are discussed. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

The Boulder Model: History, rationale, and critique.

Although the current philosophy of education in clinical psychology allows for the existence of a program of training clinical psychologists who primarily want to be practitioners in conjunction with the more traditional scientist-practitioner (Boulder model) program, the controversy over the value of the 2 types of program continues. The criticism of the Boulder model is that the rationale for requiring clinical psychology students to learn to do research as well as train to be clinicians was spurious; the Boulder model trains students as researchers, a role that is incompatible with their interests and abilities. The history of the development of the Boulder model is reviewed together with data regarding the personality traits, interests, and abilities of people interested in research as opposed to service work. Findings indicate that the objections of the critics are well founded. (6 p ref) (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Journal of Counseling Psychology (January 1973): Errata.

Reports an error in the table of contents of the Journal of Counseling Psychology. The article "On Measuring the Vocational Interests of Women" (see record 1973-23974-001) by Nancy S. Cole (1973[Mar], 20[2], 105-112) that was listed on page 16 in the January table of contents appears in this issue of the Journal. Appearing on page 16 in the January issue, in fact, is "Instability of Therapeutic Conditions in Psychotherapy" (see record 1973-21485-001), by Alan S. Gurman (1973[Jan], 20(1), 16-24). (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Ideographic Concept Mapping in Counseling Psychology Research: Conceptual Overview, Methodology, and an Illustration.

This article provides an overview of the research approach called concept mapping at conceptual, methodological, and practical levels. The relevance of the approach to counseling psychology research is discussed, and the approach is located conceptually in the realm of qualitative methods available to counseling psychology researchers. To illustrate ideographic concept mapping, the authors collect, present, and discuss data from 2 psychologists regarding their conception of the scientist-practitioner construct. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Short report: ramipril and hydrochlorothiazide combination therapy in hypertension: a clinical trial of factorial design. The East Germany Collaborative Trial Group

OBJECTIVE: To identify appropriate dosages of ramipril and hydrochlorothiazide (HCT) when given in combination once a day for the treatment of essential hypertension. DESIGN: A 2- or 4-week placebo run-in followed by 6-week, double-blind, parallel-group phase: 4 x 3 factorial (2.5, 5 and 10 mg ramipril; 12.5 and 25 mg HCT; all six combinations; placebo). SETTING: Office practice (21 centres). PATIENTS AND PARTICIPANTS: Patients with mild-to-moderate essential hypertension (World Health Organization stage I-II; supine diastolic blood pressure 100-115 mmHg in last 2 weeks of run-in): 581 enrolled, 534 randomly assigned to double-blind therapy and 517 completed. MAIN OUTCOME MEASURES: Reduction in supine and standing blood pressure. RESULTS: In pairwise comparisons, the combinations of 5 mg ramipril with 12.5 and 25 mg HCT and 10 mg ramipril with 12.5 mg HCT consistently produced significantly greater blood pressure reductions than their respective components. Response surface analyses were performed, and a stairstep model was constructed to characterize the shape of the dose-response surface. The combinations involving 5 and 10 mg ramipril with 12.5 and 25 mg HCT were again more effective than their components. Withdrawals and adverse effects were minimal for all treatments. A large drop in serum potassium was observed on 25 mg HCT, but not on combination therapy. Addition of ramipril appeared to reduce the hyperuricaemic effect of HCT. CONCLUSIONS: Several dosage combinations of ramipril plus HCT produced significantly greater blood pressure reductions than the monotherapies at the same dosages. Overall, the combination of 5 mg ramipril and 25 mg HCT gave the best mean reduction. Combination therapy with ramipril plus HCT was safe and effective for patients with mild-to-moderate essential hypertension.