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D Spiegelman

Publications and source records attributed to D Spiegelman.

At least 73 records · Page 4Linked to original sources
PubMed2000

Prospective study of major dietary patterns and risk of coronary heart disease in men.

BACKGROUND: Previous studies on diet and coronary heart disease (CHD) focused primarily on individual nutrients or foods. OBJECTIVE: We examined whether overall dietary patterns derived from a food-frequency questionnaire (FFQ) predict risk of CHD in men. DESIGN: This was a prospective cohort study of 44875 men aged 40-75 y without diagnosed cardiovascular disease or cancer at baseline in 1986. RESULTS: During 8 y of follow-up, we documented 1089 cases of CHD (nonfatal myocardial infarction and fatal CHD). Using factor analysis, we identified 2 major dietary patterns using dietary data collected through a 131-item FFQ. The first factor, which we labeled the "prudent pattern," was characterized by higher intake of vegetables, fruit, legumes, whole grains, fish, and poultry, whereas the second factor, the "Western pattern," was characterized by higher intake of red meat, processed meat, refined grains, sweets and dessert, French fries, and high-fat dairy products. After adjustment for age and CHD risk factors, the relative risks from the lowest to highest quintiles of the prudent pattern score were 1.0, 0. 87, 0.79, 0.75, and 0.70 (95% CI: 0.56, 0.86; P: for trend = 0.0009). In contrast, the relative risks across increasing quintiles of the Western pattern score were 1.0, 1.21, 1.36, 1.40, and 1.64 (95% CI: 1.24, 2.17; P: for trend < 0.0001). These associations persisted in subgroup analyses according to cigarette smoking, body mass index, and parental history of myocardial infarction. CONCLUSIONS: These data suggest that major dietary patterns derived from the FFQ predict risk of CHD, independent of other lifestyle variables.

Adult↗
PubMed2000

Adherence to the Dietary Guidelines for Americans and risk of major chronic disease in men.

BACKGROUND: The Dietary Guidelines for Americans and the food guide pyramid aim to reduce the risk of major chronic disease in the United States, but data supporting their overall effectiveness are sparse. The healthy eating index (HEI) measures the concordance of dietary patterns with these guidelines. OBJECTIVE: We tested whether a high HEI score (range: 0-100; 100 is best) calculated from a validated food-frequency questionnaire (HEI-f) could predict lower risk of major chronic disease in men. DESIGN: A cohort of US male health professionals without major disease completed detailed questionnaires on food intake and other risk factors for heart disease and cancer in 1986 and repeatedly during the 8-y follow-up. Major chronic disease outcome was defined as incident major cardiovascular disease (stroke or myocardial infarction, n = 1092), cancer (n = 1661), or other non-trauma-related deaths (n = 366). RESULTS: The HEI-f was weakly inversely associated with risk of major chronic disease [comparing highest with lowest quintile of the HEI-f, relative risk (RR) = 0.89; 95% CI: 0.79, 1.00; P: < 0.001 for trend]. The HEI-f was associated with moderately lower risk of cardiovascular disease (RR = 0.72; 95% CI: 0.60, 0.88; P: < 0.001) but was not associated with lower cancer risk. CONCLUSIONS: The HEI-f was only weakly associated with risk of major chronic disease, suggesting that improvements to the HEI may be warranted. Further research on the HEI could have implications for refinements to the Dietary Guidelines for Americans and the food guide pyramid.

Alcohol Drinking↗
PubMed2000

Nutritional factors and infectious disease contribute to anemia among pregnant women with human immunodeficiency virus in Tanzania.

The objective of this cross-sectional study was to identify risk factors for anemia among human immunodeficiency virus (HIV)-positive pregnant women in Dar es Salaam, Tanzania. Baseline data from 1064 women enrolled in a clinical trial on the effect of vitamin supplementation in HIV infection were examined to identify potential determinants of anemia. The mean hemoglobin (Hb) level was 94 g/L, and the prevalence of severe anemia (Hb < 85 g/L) was 28%; 83% of the women had Hb < 110 g/L. Iron deficiency and infectious disease appeared to be the predominant causes of anemia. Significant independent associations with severe anemia were observed for women with body mass index (BMI) < 19 kg/m(2) compared with women with BMI > 24 kg/m(2) [odds ratio (OR) 3.13, 95% confidence interval (CI): 1. 37-7.14); malaria parasite densities > 1000/mm(3) (OR 2.70, CI: 1. 58-4.61) compared with women with no parasites; eating soil during early pregnancy (OR 2.47, CI: 1.66-3.69); CD4+ cell count < 200/microL compared with CD4+ count > 500/microL (OR 2.70, CI: 1. 42-5.12); and serum retinol levels < 70 micromol/L (OR 2.45, CI: 1. 44-4.17) compared with women with retinol levels > 1.05 micromol/L. The most significant risk factors associated with severe anemia in this population are preventable. Public health recommendations include increasing the effectiveness of iron supplementation and malaria management during pregnancy, and providing health education messages that increase awareness of the potentially adverse nutritional consequences of eating soil during pregnancy.

Adult↗
PubMed2000

Diarrhea and abnormalities of gastrointestinal function in a cohort of men and women with HIV infection.

OBJECTIVE: The aim of this study was to determine the prevalence of gastrointestinal dysfunction in the era of improved treatment of HIV infection. METHODS: Gastrointestinal function was studied cross-sectionally in 671 persons with HIV. Absorptive function was measured by a 25-g D-xylose test, a Sudan-III stain for fecal fat on a 100-g fat diet, and serum levels of micronutrients. RESULTS: Eighty-eight percent had at least one abnormality of gastrointestinal function: 47.7% had low D-xylose absorption; 40.3% had a history of liver disease; 38.9% had diarrhea; 28.3% had chronic diarrhea; 22.5% had borderline or low serum vitamin B12 levels; 12.2% had stool pathogens; and 7.2% were hypoalbuminemic. Men were more likely to have low D-xylose absorption, diarrhea, and stool pathogens than women. Intravenous drug users (IVDUs) were more likely to have a history of liver disease and hypoalbuminemia. However, borderline or low vitamin B12 levels were less frequent in IVDUs; they tended to have less diarrhea and a lower prevalence of stool pathogens. Despite less history of liver disease, 14.1% of women were hypoalbuminemic. Differences in patterns of gastrointestinal dysfunction are unlikely to be due to severity of immunosuppression as abnormalities were seen in all risk groups with CD4 >200 cells/mm3. D-xylose absorption below 30 mg/dl, current diarrhea, and borderline levels of vitamin B12 were associated with advanced immunosuppression. CONCLUSIONS: Abnormalities of gastrointestinal function are common in the current era of HIV treatment, appear early in the course of HIV infection, and in the absence of diarrhea. Gender and IVDU are important determinants of the type and frequency of gastrointestinal abnormalities.

Adult↗
PubMed2000

Measurement error correction using validation data: a review of methods and their applicability in case-control studies.

Measurement error is a serious problem in the analysis of epidemiological data. In the past 20 years, a large number of methods for the correction of measurement error have been developed. While at the beginning mostly methods for cohort studies were considered, recently more attention has been paid to case-control studies. Although a variety of methods have been proposed, they are very rarely used in practice. To stimulate their use and further development, this article provides a comprehensive overview on methods developed for multivariable regression analysis of epidemiologic studies with validation data sets. The methods are systematically classified with respect to the underlying theory. An assessment of prerequisites, assumptions and performance of the available methods is given. Particular attention is paid to applicability to case-control studies and need for further research and development is pointed out.

Bias↗
PubMed2000

Predictors of change in the functional status of children with human immunodeficiency virus infection.

OBJECTIVE: The purpose of this study was to identify important clinical predictors of change in the functional status of children with perinatally acquired human immunodeficiency virus (HIV) infection. METHODS: Children who were perinatally exposed to HIV underwent evaluation of growth, nutritional, and functional status parameters as part of a prospective study of HIV and nutrition in children. The main outcome measures for HIV-infected children were change over time in: 1) Total Health, 2) General Health, and 3) Responsiveness as measured by the Functional Status II(R) (FSII[R]). Candidate predictors included anthropometric measurements, social factors, HIV disease stage, CD4 T lymphocyte count, medications, and other clinical markers of illness. RESULTS: The parents or legal guardians of 35 perinatally HIV-infected children completed 2 FSII(R) surveys over a mean of 16 months. Functional Status scores were significantly correlated with number of times and days hospitalized in the past 6 months and with illness at the time of baseline evaluation. Functional status declined overtime on all 3 scales; however, only the change in Total Health score was statistically significant. Total, General Health, and Responsiveness scores declined by >/=5 points in 20.0%, 17.1%, and 14.3% of children, respectively. Significant univariate predictors of change in at least 1 component of the functional status survey included race, guardianship, height z score, prescription of antiviral medications other than antiretrovirals, and illness at time of baseline evaluation. In multivariate models, adjusting for baseline score and biologic relationship of guardian completing survey, significant predictors of a decline in Total Health scores included non-white race and lower baseline height z score. The General Health score declined with lower baseline absolute CD4 count and lower baseline height z score. Finally, Responsiveness scores declined in children whose guardian was their biologic parent and in children with lower baseline height z scores. CONCLUSION: The FSII(R) questionnaire correlates with other markers of disease severity in children with HIV infection. Growth parameters, immune status, and social factors are important predictors of functional status in HIV-infected children.

Activities of Daily Living↗
PubMed2000

Vitamin A supplementation and other predictors of anemia among children from Dar Es Salaam, Tanzania.

The associations of hemoglobin, hematocrit, and packed cell volume with socioeconomic factors, malaria, human immunodeficiency virus (HIV) infection, and nutritional status were examined among 687 children admitted to hospital with pneumonia participating in a double blind, placebo-controlled trial of vitamin A supplementation. Children were randomized to receive 2 doses of vitamin A (200,000 IU) or placebo at baseline, and additional doses at 4 and 8 months after discharge from hospital. Hemoglobin levels were measured at enrollment and, on a subset of 161 children, during follow-up. At baseline, hemoglobin concentration was positively associated with the number of possessions in the household, maternal level of education and quality of water supply, and inversely related to malaria infection after controlling for potential confounding variables. Children infected with HIV experienced a significant fall in mean hemoglobin levels over time. The risk of developing severe anemia (< 7 g/dL) during follow-up was lower for children who were breastfed for longer than 18 months as compared to those with less than 6 months of breastfeeding (adjusted prevalence ratio = 0.14, 95% confidence interval [CI] = 0.02, 0.93; P = 0.04), and higher for children over two years of age as compared to 6 to 11 months-old infants (adjusted prevalence ratio = 8.11, 95% CI = 1.2, 55.8; P = 0.03). Children with repeated diagnoses of malaria had 4.1 times the risk of developing severe anemia than did children without the diagnosis (95% CI = 1.3, 13.5; P = 0.02). Vitamin A supplements were associated with an overall nonsignificant reduction of 14% in the risk of developing severe anemia (adjusted prevalence ratio = 0.86, 95% CI = 0.37, 1.99; P = 0.73). We conclude that malaria, HIV infection, low socioeconomic status, and short duration of breastfeeding are strong and independent determinants of adverse hematologic profiles in this population.

Anemia↗
PubMed2000

Predictors of CD4+ lymphocyte count among HIV-seropositive and HIV-seronegative pregnant women in Dar es Salaam, Tanzania.

OBJECTIVE: To determine the predictors of CD4+ lymphocyte count among pregnant women in Dar es Salaam, Tanzania. METHODS: Between 04/1995 and 03/1997, HIV-seropositive (n=1,027) and HIV-seronegative (n=280) pregnant women were interviewed to obtain socio-demographic characteristics. Later, blood samples was collected for determination of T-lymphocyte subsets and other haematological indices. RESULTS: CD4+ lymphocyte count was significantly higher among HIV-seronegative women (mean=770 cells/mm3, standard deviation (SD)=232 cells/mm3) than HIV-seropositive women (mean=422 cells/mm3, SD=205 cells/mm3). Most HIV-seropositive women were asymptomatic, in WHO clinical stage 1 (84.3%). Among HIV-seropositive women, total white blood count (WBC) and erythrocyte sedimentation rate (ESR) remained significantly correlated with CD4+ after adjusting for other predictors in multivariate analyses. For women of average age 25 years, the CD4+ lymphocyte count increased by about 16 cells/mm3 for each increment of 1000 WBC cells/mm3, while each 10 mm/hr increase in ESR was associated with a reduction of CD4+ lymphocyte count of about 8 cells/mm3. CONCLUSION: These results show that simple and inexpensive haematological indices cannot be recommended for use as alternative measures of HIV-related immunosuppression in this population of mainly asymptomatic women.

Adult↗
PubMed2000

Risk factors for HIV-1 seroprevalence among family planning clients in Dar es Salaam, Tanzania.

Between March and September of 1995, women receiving family planning (FP) services in three large clinics in Dar es Salaam, Tanzania were invited to participate in a cross-sectional study. Consenting women were interviewed to obtain information about HIV risk factors, and blood for HIV testing was collected. The prevalence of HIV was 16.9% (95% CI: 14.4%-19.3%). The risk of HIV increased significantly with age. Compared with married women, the risk of HIV was significantly higher among cohabiting women (age-adjusted OR = 2.3; 95% CI = 1.5-3.5) and among women who were single, divorced or widowed (age-adjusted OR = 2.3; 95% CI = 1.2-4.4). The risk of HIV was also significantly higher among hotel workers (age-adjusted OR = 4.3; 95% CI = 1.4-12.9). Women with laboratory evidence of sexually transmitted diseases were at increased risk of HIV. This study shows that HIV is a major public health problem among FP clients in Tanzania. Innovative HIV interventions are needed to reduce further spread of HIV infection.

Adolescent↗
PubMed2000

A prospective study of the effect of alcohol consumption and ADH3 genotype on plasma steroid hormone levels and breast cancer risk.

One suggested mechanism underlying the positive association between alcohol consumption and breast cancer risk is an influence of alcohol on steroid hormone levels. A polymorphism in alcohol dehydrogenase type 3 (ADH3) affects the kinetics of alcohol oxidation and thereby could influence the effect of alcohol consumption on hormone levels. We investigated the ADH3 polymorphism, alcohol intake, and risk of breast cancer in a nested case-control study. Among women in the Nurses' Health Study who gave a blood sample in 1989-1990, 465 incident breast cancer cases were diagnosed before June 1994 and were matched to 621 controls. Using conditional logistic regression, we calculated relative risks and confidence intervals to assess breast cancer risk for ADH3 genotype. Among postmenopausal controls not using hormones at time of blood collection, partial Pearson correlation coefficients were calculated to assess the association between alcohol intake and plasma hormone levels according to ADH3 genotype. No association was observed between ADH3 genotype and overall breast cancer risk (relative risk = 0.9 for slow oxidizers compared with fast; 95% confidence interval = 0.6-1.3). Among postmenopausal women, ADH3 genotype did not modify the weak association observed between alcohol intake and breast cancer risk (P for interaction = 0.45). Statistically significant trends in the relationship between alcohol consumption and hormone level dependent on oxidative capacity (ADH3 genotype) were observed for dehydroepiandrosterone sulfate and sex hormone-binding globulin (P < 0.05). These data suggest that the ADH3 polymorphism modestly influences the response of some plasma hormones to alcohol consumption but is not independently associated with breast cancer risk and does not modify the association between alcohol and breast cancer risk.

Adult↗
PubMed1999

Glutathione S-transferase mu and theta polymorphisms and breast cancer susceptibility.

BACKGROUND: The enzymes encoded by the glutathione S-transferase mu 1 (GSTM1) and theta 1 (GSTT1) genes are involved in the metabolism (mainly inactivation, but activation is possible) of a wide range of carcinogens that are ubiquitous in the environment; the enzyme encoded by the GSTT1 gene may also be active in endogenous mutagenic processes. Homozygous deletions of the GSTM1 and GSTT1 genes are commonly found in the population and result in a lack of enzyme activity. This study was undertaken to evaluate the association between GSTM1 and GSTT1 gene polymorphisms and breast cancer risk. METHODS: Our study included 466 women with incident cases of breast cancer occurring from May 1989 through May 1994 and 466 matched control subjects. These individuals were part of a prospective cohort of U.S. women (i.e., the Nurses' Health Study). Odds ratios (ORs) and 95% confidence intervals (CIs) from conditional logistic regression models were used to estimate the association between genetic polymorphisms and breast cancer risk. RESULTS: The GSTM1 and GSTT1 null genotypes were not associated with an increased risk of breast cancer (OR = 1.05 [95% CI = 0.80-1.37] for GSTM1 null; OR = 0. 86 [95% CI = 0.61-1.21] for GSTT1 null). On the contrary, a suggestion of a decreased risk of breast cancer associated with the GSTT1 null genotype was observed among premenopausal women. When considered together, no combination of the GSTM1 and GSTT1 genotypes was associated with an increased risk of breast cancer. The relationship between GSTM1 and GSTT1 gene deletions and breast cancer risk was not substantially modified by cigarette smoking. CONCLUSIONS: Our data provide evidence against a substantially increased risk of breast cancer associated with GSTM1 and/or GSTT1 homozygous gene deletions.

Breast Neoplasms↗
PubMed1999

Fruit and vegetable intake in relation to risk of ischemic stroke.

CONTEXT: Few studies have evaluated the relationship between fruit and vegetable intake and cardiovascular disease. OBJECTIVE: To examine the associations between fruit and vegetable intake and ischemic stroke. DESIGN, SETTING, AND SUBJECTS: Prospective cohort studies, including 75 596 women aged 34 to 59 years in the Nurses' Health Study with 14 years of follow-up (1980-1994), and 38683 men aged 40 to 75 years in the Health Professionals' Follow-up Study with 8 years of follow-up (1986-1994). All individuals were free of cardiovascular disease, cancer, and diabetes at baseline. MAIN OUTCOME MEASURE: Incidence of ischemic stroke by quintile of fruit and vegetable intake. RESULTS: A total of 366 women and 204 men had an ischemic stroke. After controlling for standard cardiovascular risk factors, persons in the highest quintile of fruit and vegetable intake (median of 5.1 servings per day among men and 5.8 servings per day among women) had a relative risk (RR) of 0.69 (95% confidence interval [CI], 0.52-0.92) compared with those in the lowest quintile. An increment of 1 serving per day of fruits or vegetables was associated with a 6% lower risk of ischemic stroke (RR, 0.94; 95 % CI, 0.90-0.99; P =.01, test for trend). Cruciferous vegetables (RR, 0.68 for an increment of 1 serving per day; 95% CI, 0.49-0.94), green leafy vegetables (RR, 0.79; 95% CI, 0.62-0.99), citrus fruit including juice (RR, 0.81; 95% CI, 0.68-0.96), and citrus fruit juice (RR, 0.75; 95% CI, 0.61-0.93) contributed most to the apparent protective effect of total fruits and vegetables. Legumes or potatoes were not associated with lower ischemic stroke risk. The multivariate pooled RR for total stroke was 0.96 (95% CI, 0.93-1.00) for each increment of 2 servings per day. CONCLUSIONS: These data support a protective relationship between consumption of fruit and vegetables-particularly cruciferous and green leafy vegetables and citrus fruit and juice-and ischemic stroke risk.

Adult↗
PubMed1999

Recreational physical activity and the risk of cholecystectomy in women.

BACKGROUND: Physical activity may be an important determinant of the risk of gallstone disease in women, both independently and as a result of its role in maintaining body weight. METHODS: We prospectively studied recreational physical activity (such as jogging, running, and bicycling) and sedentary behavior (such as spending hours watching television) in relation to the risk of cholecystectomy, a surrogate for symptomatic cholelithiasis, in a cohort of 60,290 women who were 40 to 65 years of age in 1986 and had no history of gallstone disease. As part of the Nurses' Health Study, the women reported on questionnaires mailed to them every two years both their activity level and whether they had undergone cholecystectomy. During a 10-year follow-up period (1986 to 1996), 3257 cases of cholecystectomy were documented. RESULTS: Recreational physical activity was inversely related to the risk of cholecystectomy. The multivariate relative risk for women in the highest as compared with the lowest quintile of physical activity was 0.69 (95 percent confidence interval, 0.61 to 0.78). In contrast, sedentary behavior was independently related to an increased risk of cholecystectomy. As compared with women who spent less than 6 hours per week sitting while at work or driving, women who spent 41 to 60 hours per week sitting had a multivariate relative risk of 1.42 (95 percent confidence interval, 1.06 to 1.89), and women who spent more than 60 hours per week sitting while at work or driving had a multivariate relative risk of 2.32 (95 percent confidence interval, 1.26 to 4.26). These associations persisted after we controlled for body weight and weight change. CONCLUSIONS: In women, recreational physical activity is associated with a decreased risk of cholecystectomy. The association is independent of other risk factors for gallstone disease, such as obesity and recent weight loss.

Adult↗
PubMed1999

Risk factors for basal cell carcinoma of the skin in men: results from the health professionals follow-up study.

The authors examined the relation of constitutional factors and sun exposure to risk of basal cell carcinoma of the skin (BCC) in a prospective cohort of 44,591 predominantly Caucasian US male health professionals, 40-75 years of age and free of cancer at enrollment in 1986. During 8 years of follow-up, 3,273 cases of self-reported BCC were documented. The following variables were each associated with an elevated risk of BCC: having red hair; green, hazel, or blue eyes; a tendency to sunburn; and north European ancestry. The lifetime number of blistering sunburns was also positively associated with BCC risk (p trend < 0.0001). Compared with men who as teenagers had been outside less than once a week, men who had been outside weekly (relative risk (RR) = 1.30; 95% confidence interval (CI): 1.14, 1.47) and daily (RR = 1.42; 95% CI: 1.24, 1.63) had an elevated risk of BCC. Living in a region of residence with high solar radiation as an adult was also associated with an increased risk of BCC (RR = 1.48; 95% CI: 1.36, 1.60), whereas living in such a region only in childhood did not increase BCC risk. These results confirm the role of constitutional factors and suggest that adult sun exposure increases BCC risk.

Adult↗
PubMed1999

Evaluation of a population roster as a source of population controls: the Massachusetts Resident Lists.

Published population rosters can serve as a convenient source of population controls. The authors evaluated one such roster, the Massachusetts Resident Lists, by estimating the completeness of the Lists and by describing the differences between persons included and not included on the Lists. The subjects were cases from three case-control studies of ovarian cancer conducted in eastern Massachusetts between 1978 and 1996. For each of the three case series, more than 90% of the cases were located on the Resident Lists. Age was one of the primary differences to emerge between cases included and not included; in the most recent case series, cases younger than age 40 years were less likely than older cases to be included on the Lists.

Adult↗
PubMed1999

Elevated resting energy expenditure among HIV-seropositive persons receiving highly active antiretroviral therapy.

OBJECTIVES: To ascertain the relationships between resting energy expenditure (REE), HIV RNA in plasma, and highly active antiretroviral therapy (HAART). DESIGN: Cross-sectional analysis using data of a large cohort study of nutrition in relation to HIV disease. METHODS: HIV RNA in plasma, REE, fat-free mass (FFM), and medication regimens were assessed at 530 visits among 372 participants in a cohort study of HIV-seropositive men and women. RESULTS: HIV RNA in plasma was directly correlated with REE. After adjustment for FFM, age, CD4 cell count and HAART use, there was an increase in REE of 90 kJ/day per log10 copies/ml increase in HIV RNA [95% confidence interval (CI) 16-164; P = 0.02). HAART use had an independent effect on REE. In patients reporting HAART use, adjusted REE was 339 kJ/day higher than in those not reporting HAART use (95% CI 177-501; P = 0.0001). CONCLUSIONS: Viral load and HAART appear to exert independent effects on REE. Although HAART may decrease metabolic rate by lowering viral burden, it appears to increase metabolic demands through some mechanism(s) independent of its effect on viral burden. This may result in elevated REE despite control of viral replication.

Adult↗
PubMed1999

Evaluation of old and new tests of heterogeneity in epidemiologic meta-analysis.

The identification of heterogeneity in effects between studies is a key issue in meta-analyses of observational studies, since it is critical for determining whether it is appropriate to pool the individual results into one summary measure. The result of a hypothesis test is often used as the decision criterion. In this paper, the authors use a large simulation study patterned from the key features of five published epidemiologic meta-analyses to investigate the type I error and statistical power of five previously proposed asymptotic homogeneity tests, a parametric bootstrap version of each of the tests, and tau2-bootstrap, a test proposed by the authors. The results show that the asymptotic DerSimonian and Laird Q statistic and the bootstrap versions of the other tests give the correct type I error under the null hypothesis but that all of the tests considered have low statistical power, especially when the number of studies included in the meta-analysis is small (<20). From the point of view of validity, power, and computational ease, the Q statistic is clearly the best choice. The authors found that the performance of all of the tests considered did not depend appreciably upon the value of the pooled odds ratio, both for size and for power. Because tests for heterogeneity will often be underpowered, random effects models can be used routinely, and heterogeneity can be quantified by means of R(I), the proportion of the total variance of the pooled effect measure due to between-study variance, and CV(B), the between-study coefficient of variation.

Epidemiologic Methods↗