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Jesse A Berlin

Publications and source records attributed to Jesse A Berlin.

At least 19 recordsLinked to original sources
PubMed2007

Much ado about nothing: a comparison of the performance of meta-analytical methods with rare events.

For rare outcomes, meta-analysis of randomized trials may be the only way to obtain reliable evidence of the effects of healthcare interventions. However, many methods of meta-analysis are based on large sample approximations, and may be unsuitable when events are rare. Through simulation, we evaluated the performance of 12 methods for pooling rare events, considering estimability, bias, coverage and statistical power. Simulations were based on data sets from three case studies with between five and 19 trials, using baseline event rates between 0.1 and 10 per cent and risk ratios of 1, 0.75, 0.5 and 0.2. We found that most of the commonly used meta-analytical methods were biased when data were sparse. The bias was greatest in inverse variance and DerSimonian and Laird odds ratio and risk difference methods, and the Mantel-Haenszel (MH) odds ratio method using a 0.5 zero-cell correction. Risk difference meta-analytical methods tended to show conservative confidence interval coverage and low statistical power at low event rates. At event rates below 1 per cent the Peto one-step odds ratio method was the least biased and most powerful method, and provided the best confidence interval coverage, provided there was no substantial imbalance between treatment and control group sizes within trials, and treatment effects were not exceptionally large. In other circumstances the MH OR without zero-cell corrections, logistic regression and the exact method performed similarly to each other, and were less biased than the Peto method.

Analysis of Variance↗
PubMed2007

Risk of breast cancer associated with short-term use of oral contraceptives.

OBJECTIVE: To estimate breast cancer risk associated with short-term (<6 months) oral contraceptive use, and explore variation in estimates by use characteristics and medical, menstrual, and reproductive history. METHODS: We analyzed data from the Women's Contraceptive and Reproductive Experiences Study. Case subjects were white women and black women, 35-64 years old, diagnosed with invasive breast cancer in July 1994-April 1998. Control subjects identified by random-digit dialing were matched to case subjects by age, race, and study site. Conditional logistic regression was used to estimate odds ratios (ORs) and 95% confidence intervals (CIs). RESULTS: Overall, short-term oral contraceptive use was not associated with breast cancer risk (OR = 1.0; 95% CI = 0.8-1.1). However, significant interaction between short-term use and menopausal status led to an observed increased breast cancer risk in pre-menopausal women (OR = 1.3; 95% CI = 1.0-1.7) and a reduced risk in post-menopausal women (OR = 0.8; 95% CI = 0.6-1.0) associated with short-term use. The association was more pronounced in women with non-contraceptive reasons for use and underlying risk factors for breast cancer. CONCLUSIONS: These associations may result from underlying characteristics of users or unmeasured factors influencing duration of use and breast cancer risk.

Adult↗
PubMed2006

Case-control study of postmenopausal hormone replacement therapy and endometrial cancer.

This study evaluated recent inconsistent findings that adding progestins to postmenopausal estrogen replacement therapy protects against endometrial cancer. Using a population-based case-control study, the authors compared 511 endometrial cancer cases aged 50-79 years in the Philadelphia, Pennsylvania, region during 1999-2002 with 1,412 random-digit-dialing controls regarding postmenopausal hormone replacement therapy (HRT) use. Telephone interviews were performed with memory aids mailed in advance. An increased risk of endometrial cancer was observed among postmenopausal women using only unopposed estrogen for 3 or more years, compared with women who never used HRT (adjusted odds ratio = 3.4, 95% confidence interval (CI): 1.4, 8.3). Using combination HRT (of any duration) was associated with a substantial reduction in risk (odds ratio = 0.8, 95% CI: 0.6, 1.1). Comparing women using only combined estrogen and progestin for 3 or more years with women using only unopposed estrogen for 3 or more years, the authors found that the adjusted odds ratio was 0.2 (95% CI: 0.1, 0.6). Long-term use of unopposed estrogen is associated with increased risk for endometrial cancer, whereas combined estrogen plus progestin hormone therapy is not. Thus, if HRT is to be used in women with an intact uterus, this study confirms the benefit of adding progestins to the regimen.

Aged↗
PubMed2006

Estrogen sulfation genes, hormone replacement therapy, and endometrial cancer risk.

BACKGROUND: Unopposed estrogen replacement therapy is associated with increased risk of endometrial cancer. To investigate the mechanism of this association, we evaluated whether risk of endometrial cancer was associated with the genotypes involved in steroid hormone metabolism and the duration of exogenous hormone use. METHODS: A population-based case-control study in nine counties of the Philadelphia metropolitan area was undertaken with 502 case patients with endometrial cancer and 1326 age- and race-matched control subjects. Data regarding exogenous hormone use were obtained by interview, and genotypes of the genes COMT, CYP1A1, CYP1A2, CYP1B1, CYP3A4, PGR, SULT1A1, SULT1E1, and UGT1A1 were obtained by polymerase chain reaction techniques. Conditional logistic regression was used to examine the relationship among genotype, hormone use, and endometrial cancer risk. RESULTS: Associations were observed between the risk of endometrial cancer and genotypes of the following steroid hormone metabolism genes: CYP1A1*2C (adjusted odds ratio [OR] = 1.68, 95% confidence interval [CI] = 1.08 to 2.61); SULT1A1*3 (adjusted OR = 0.51, 95% CI = 0.29 to 0.92); and the G --> A variant in the promoter of SULT1E1 at position -64 (adjusted OR = 1.45, 95% CI = 1.06 to 1.99). We observed a statistically significant interaction between estrogen replacement therapy use and SULT1A1*2 genotype: the SULT1A1*2 allele and long-term use of estrogen replacement therapy were associated with statistically significantly higher risk of endometrial cancer (adjusted OR = 3.85, 95% CI = 1.48 to 10.00) than that of the SULT1A1*2 allele and no estrogen replacement therapy use. CONCLUSIONS: Among women with long-term use of estrogen replacement therapy or combined hormone replacement therapy, the risk of endometrial cancer may be associated with functionally relevant genotypes that regulate steroid hormone sulfation.

Aryl Hydrocarbon Hydroxylases↗
PubMed2006

Longitudinal and repeated cross-sectional cluster-randomization designs using mixed effects regression for binary outcomes: bias and coverage of frequentist and Bayesian methods.

As medical applications for cluster randomization designs become more common, investigators look for guidance on optimal methods for estimating the effect of group-based interventions over time. This study examines two distinct cluster randomization designs: (1) the repeated cross-sectional design in which centres are followed over time but patients change, and (2) the longitudinal design in which individual patients are followed over time within treatment clusters. Simulations of each study design stipulated a multiplicative treatment effect (on the log odds scale), between 5 and 15 clusters in each of two treatment arms, and followed over two time periods. Estimation options included linear mixed effects models using restricted maximum likelihood (REML), generalized estimating equations (GEE), mixed effects logistic regression using both penalized quasi likelihood (PQL) and numerical integration, and Bayesian Monte Carlo analysis. For the repeated cross-sectional designs, most methods performed well in terms of bias and coverage when clusters were numerous (30) and variability across clusters of baseline risk and treatment effect was modest. With few clusters (two groups of five) and higher variability, only the Bayesian methods maintained coverage. In the longitudinal designs, the common methods of REML, GEE, or PQL performed poorly when compared to numerical integration, while Bayesian methods demonstrated less bias and better coverage for estimates of both log odds ratios and risk differences. The performance of common statistical tools for the analysis of cluster randomization designs depends heavily on the precise design, the number of clusters, and the variability of baseline outcomes and treatment effects across centres.

Bayes Theorem↗
PubMed2006

Insulin sensitizing pharmacotherapy for prevention of myocardial infarction in patients with diabetes mellitus.

Type 2 diabetes mellitus and insulin resistance are associated with an increased risk of myocardial infarction (MI). Although differences exist in insulin sensitization among oral hypoglycemic drugs, it is unclear whether these differences translate into a differential risk of MI and whether differences exist among these drugs. We conducted a case-control study of first MI in a 5-county area during a 56-month period. The patients were those with type 2 diabetes mellitus hospitalized with a first MI and the controls were those with diabetes mellitus randomly selected from the same geographic area. Information on medication use and other clinical data were obtained by telephone interview. After adjustment for all confounders, the odds ratio for MI for current monotherapy with thiazolidinedione and monotherapy with metformin compared with monotherapy with sulfonylurea was 0.33 (95% confidence interval 0.12 to 0.92, p = 0.03) and 0.48 (95% confidence interval 0.27 to 0.82, p = 0.01), respectively. The addition of a thiazolidinedione, but not metformin, to sulfonylurea monotherapy was associated with a significant reduction in MI risk compared with sulfonylurea therapy alone. In conclusion, the use of insulin-sensitizing drugs is associated with a significantly reduced risk of MI compared with sulfonylurea use, and the addition of a thiazolidinedione to sulfonylurea monotherapy is associated with a lower risk of MI.

Adult↗
PubMed2006

A randomized controlled trial of financial incentives for smoking cessation.

BACKGROUND: Although 435,000 Americans die each year of tobacco-related illness, only approximately 3% of smokers quit each year. Financial incentives have been shown to be effective in modifying behavior within highly structured settings, such as drug treatment programs, but this has not been shown in treating chronic disease in less structured settings. The objective of this study was to determine whether modest financial incentives increase the rate of smoking cessation program enrollment, completion, and quit rates in a outpatient clinical setting. METHODS: 179 smokers at the Philadelphia Veterans Affairs Medical Center who reported smoking at least 10 cigarettes per day were randomized into incentive and non-incentive groups. Both groups were offered a free five-class smoking cessation program at the Philadelphia Veterans Affairs Medical Center. The incentive group was also offered $20 for each class attended and $100 if they quit smoking 30 days post program completion. Self-reported smoking cessation was confirmed with urine cotinine tests. RESULTS: The incentive group had higher rates of program enrollment (43.3% versus 20.2%; P<0.001) and completion (25.8% versus 12.2%; P=0.02). Quit rates at 75 days were 16.3% in the incentive group versus 4.6% in the control group (P=0.01). At 6 months, quit rates in the incentive group were not significantly higher (6.5%) than in the control group (4.6%; P>0.20). CONCLUSION: Modest financial incentives are associated with significantly higher rates of smoking cessation program enrollment and completion and short-term quit rates. Future studies should consider including an incentive for longer-term cessation.

Cotinine↗
PubMed2005

Lifetime recreational exercise activity and breast cancer risk among black women and white women.

BACKGROUND: Physical inactivity is a potentially modifiable breast cancer risk factor. Because few data on this relationship exist for black women, we examined the relationship between breast cancer risk and lifetime and time- or age-specific measures of recreational exercise activity among white women and among black women. METHODS: The Women's Contraceptive and Reproductive Experiences Study was a multicenter population-based case-control study of black women and white women aged 35-64 years with newly diagnosed invasive breast cancer. We collected detailed histories of lifetime recreational exercise activity during in-person interviews with 4538 case patients with breast cancer (1605 black and 2933 white) and 4649 control subjects (1646 black and 3033 white). Control subjects were frequency-matched to case patients on age, race, and study site. We examined associations between exercise activity measures (metabolic equivalents of energy expenditure [MET]-hours per week per year) and breast cancer risk overall and among subgroups defined by race, other breast cancer risk factors, and tumor characteristics by use of unconditional logistic regression. All statistical tests were two-sided. RESULTS: Among all women, decreased breast cancer risk was associated with increased levels of lifetime exercise activity (e.g., average MET-hours per week per year, P(trend) = .002). An average annual lifetime exercise activity that was greater than the median level for active control subjects was associated with an approximately 20% lower risk of breast cancer, compared with that for inactivity (for 6.7-15.1 MET-hours/week/year, odds ratio [OR] = 0.82, 95% confidence interval [CI] = 0.71 to 0.93; for > or =15.2 MET-hours/week/year, OR = 0.80, 95% CI = 0.70 to 0.92). The inverse associations did not differ between black and white women (for MET-hours/week/year, P(trend) = .003 and P(trend) = .09, respectively; homogeneity of trends P = .16). No modification of risk was observed by disease stage, estrogen receptor status, or any breast cancer risk factor other than first-degree family history of breast cancer. CONCLUSIONS: This study supports an inverse association between physical activity and breast cancer among black women and among white women.

Adolescent↗
PubMed2005

The epidemiology and attributable outcomes of candidemia in adults and children hospitalized in the United States: a propensity analysis.

BACKGROUND: Candida species are the fourth most common cause of bloodstream infection and are the leading cause of invasive fungal infection among hospitalized patients in the United States. However, the frequency and outcomes attributable to the infection are uncertain. This retrospective study set out to estimate the incidence of candidemia in hospitalized adults and children in the United States and to determine attributable mortality, length of hospital stay, and hospital charges related to candidemia. METHODS: We used the Nationwide Inpatient Sample 2000 for adult patients and the Kids' Inpatient Database 2000 for pediatric patients. We matched candidemia-exposed and candidemia-unexposed patients by the propensity scores for the probability of candidemia exposure, which were derived from patient characteristics. Attributable outcomes were calculated as the differences in estimates of outcomes between propensity score-matched patients with and without candidemia. RESULTS: In the United States in 2000, candidemia was diagnosed in an estimated 1118 hospital admissions of pediatric patients and 8949 hospital admissions of adult patients, yielding a frequency of 43 cases per 100,000 pediatric admissions (95% confidence interval [CI], 35-52 cases per 100,000 pediatric admissions) and 30 cases per 100,000 adult admissions (95% CI, 26-34 cases per 100,000 adult admissions). In pediatric patients, candidemia was associated with a 10.0% increase in mortality (95% CI, 6.2%-13.8%), a mean 21.1-day increase in length of stay (95% CI, 14.4-27.8 days), and a mean increase in total per-patient hospital charges of 92,266 dollars (95% CI, 65,058 dollars-119,474 dollars). In adult patients, candidemia was associated with a 14.5% increase in mortality (95% CI, 12.1%-16.9%), a mean 10.1-day increase in length of stay (95% CI, 8.9-11.3 days), and a mean increase in hospital charges of 39,331 dollars (95% CI, 33,604 dollars-45,602 dollars). CONCLUSION: The impact of candidemia on excess mortality, increased length of stay, and the burden of cost of hospitalization underscores the need for improved means of prevention and treatment of candidemia in adults and children.

Aged↗
PubMed2005

Patients exposed to rofecoxib and celecoxib have different odds of nonfatal myocardial infarction.

BACKGROUND: Studies have postulated that cyclooxygenase-2 (COX-2) selective inhibitors affect cardiovascular risk through various mechanisms. Some of these mechanisms could increase risk (for example, inhibition of prostacyclin production), and some could decrease risk (for example, inhibition of inflammation). OBJECTIVE: To determine the effect of COX-2 inhibitors on risk for nonfatal myocardial infarction (MI). DESIGN: Case-control study. SETTING: 36 hospitals in a 5-county area. PARTICIPANTS: 1718 case-patients with a first, nonfatal MI admitted to these hospitals and 6800 controls randomly selected from the same counties. MEASUREMENTS: Self-reported medication use assessed through telephone interviews. RESULTS: The adjusted odds ratio for MI among celecoxib users, relative to persons who did not use nonaspirin nonsteroidal anti-inflammatory drugs (NSAIDs), was 0.43 (95% CI, 0.23 to 0.79) compared with 1.16 (CI, 0.70 to 1.93) among rofecoxib users. The use of rofecoxib was associated with a statistically significant higher odds of MI compared with the use of celecoxib (adjusted odds ratio for rofecoxib vs. celecoxib, 2.72 [CI, 1.24 to 5.95]; P = 0.01). Nonselective NSAIDs were associated with a reduced odds of nonfatal MI relative to nonusers. Comparisons of COX-2 inhibitors with nonselective NSAIDs were the following: rofecoxib versus naproxen (odds ratio, 3.39 [CI, 1.37 to 8.40]) and celecoxib versus ibuprofen or diclofenac (odds ratio, 0.77 [CI, 0.40 to 1.48]). LIMITATIONS: The possibility of recall bias and uncontrolled confounding in this observational study limit the ability to make definitive conclusions. The association of celecoxib with a lower odds of MI could have occurred by chance. Only about 50% of eligible participants completed telephone interviews. CONCLUSION: Celecoxib and rofecoxib were associated with different odds of MI. Cardiovascular effects among the COX-2 inhibitors seem different, but further studies, preferably randomized trials, are needed to fully understand the spectrum of effects of COX-2 inhibitors and potential differences among them.

Aged↗
PubMed2005

Prevalence and treatment of psoriasis in the United Kingdom: a population-based study.

OBJECTIVE: To measure the prevalence and treatment of psoriasis in the United Kingdom. DESIGN: Cross-sectional study to determine prevalence and cohort study to determine treatment patterns. SETTING: Outpatient practices of general practitioners. PATIENTS: We included in the analysis all patients who were registered with a general practitioner in the General Practice Research Database from 1987 to 2002. MAIN OUTCOME MEASURES: The prevalence and treatment of psoriasis. RESULTS: We identified 114 521 patients with psoriasis of a total population of 7 533 475 patients, yielding a prevalence of 1.5%. The prevalence of psoriasis increases more rapidly in young female patients compared with young male patients and declines significantly in patients 70 years and older, regardless of sex. Overall, 91.8% of patients with a diagnosis of psoriasis received a prescription for psoriasis treatment on or after the date of their first diagnostic code of psoriasis in the General Practice Research Database. Most of the patients (55.2%) received only 1 or 2 prescriptions for psoriasis in the first year after psoriasis was documented in the General Practice Research Database. CONCLUSIONS: The epidemiology of psoriasis in the General Practice Research Database population is similar to that of other epidemiologic studies of psoriasis performed in the United Kingdom, the United States, and other Western countries. Psoriasis carries a substantial burden given its high prevalence and its associated need for prescription therapy. Additional studies are necessary to determine why the prevalence of psoriasis increases more rapidly in female patients and to determine why the prevalence decreases in patients 70 years and older.

Adolescent↗
PubMed2005

Antibiotic treatment of acne may be associated with upper respiratory tract infections.

OBJECTIVE: To determine if the long-term use of antibiotics for the treatment of acne results in an increase in either of 2 common infectious illnesses: upper respiratory tract infections (URTIs) or urinary tract infections. DESIGN: Retrospective cohort study. SETTING: General Practice Research Database of the United Kingdom, London, England, from 1987 to 2002. PATIENTS: Patients with a diagnosis of acne. MAIN OUTCOME MEASURE: The onset of either a URTI or a urinary tract infection. RESULTS: Of 118 496 individuals with acne (age range, 15-35 years) who were identified in the General Practice Research Database, 84 977 (71.7%) received a topical or oral antibiotic (tetracyclines, erythromycin, or clindamycin) for treatment of their acne and 33 519 (28.3%) did not. Within the first year of observation, 18 281 (15.4%) of the patients with acne had at least 1 URTI, and within that year, the odds of a URTI developing among those receiving antibiotic treatment were 2.15 (95% confidence interval, 2.05-2.23; P<.001) times greater than among those who were not receiving antibiotic treatment. Multiple additional analyses, which were conducted to show that this effect was not an artifact of increased health care-seeking behavior among our cohorts, included comparing the cohorts of patients with acne with a cohort of patients with hypertension and the likelihood of developing a urinary tract infection. CONCLUSIONS: Patients with acne who were receiving antibiotic treatment for acne were more likely to develop a URTI than those with acne who were not receiving such treatment. The true clinical importance of our findings will require further investigation.

Acne Vulgaris↗
PubMed2005

Epidemiologic studies of adverse effects of anti-retroviral drugs: how well is statistical power reported.

PURPOSE: To determine whether there is a difference in average statistical power between pharmacoepidemiologic studies of anti-retroviral adverse drug effects (ADEs) sponsored by for-profit versus non-profit organizations. METHODS: We studied all published pharmacoepidemiologic studies of ADEs associated with the 15 anti-retroviral drugs approved through the end of 1999. A priori, the primary outcome was the power of each study to detect a clinically important difference in the risk for an adverse effect among patients exposed to the study drug(s). We could not evaluate this outcome because of the infrequent reporting of power calculations. We instead report the distribution of studies across a 5-tiered measure of adequacy of reporting of statistical power, as well as the sponsorship of these studies. RESULTS: Of 48 studies meeting our inclusion criteria, only 1 (2%) reported either a completed, a priori power calculation or sufficient details for readers to calculate the power to detect a pre-defined, clinically important effect. Thirty-five studies (73%) reported the minimum information required for sophisticated readers to determine the power to detect an event rate of interest to them; 6 additional studies (13%) reported confidence intervals around at least one summary effect measure and 6 (13%) provided no indication of power or uncertainty. Of the 41 studies for which sponsorship was determined, only 3 (7%) were sponsored by for-profit organizations. CONCLUSIONS: The poor reporting of statistical power in this sample suggests a need for guidelines to improve the reporting of pharmacoepidemiologic studies of ADEs. Future research is needed to determine whether the observed paucity of industry-sponsored observational studies of anti-retroviral ADEs extends to other clinical areas, and if so, to identify the causes of this phenomenon.

Adverse Drug Reaction Reporting Systems↗
PubMed2005

Potential limitations of electronic database studies of prescription non-aspirin non-steroidal anti-inflammatory drugs (NANSAIDs) and risk of myocardial infarction (MI).

PURPOSE: To determine whether specific limitations in electronic database studies may lead to biased estimates of the association between prescription, non-selective non-aspirin non-steroidal anti-inflammatory drugs (NANSAIDs) and myocardial infarction (MI) METHODS: Using our case-control study of NANSAIDs and first, non-fatal MI, we determined the odds ratio (OR) for prescription NANSAIDs and MI. In the 'Replicating Electronic Database Analysis,' we considered non-prescription NANSAID users to be 'non-users,' did not stratify by aspirin use, and did not adjust for confounders typically unavailable or incomplete in existing databases. In the 'Misclassification Assessment Analysis,' we removed non-prescription NANSAIDs from the 'non-user' category. In the 'Confounding Assessment Analysis #1,' we additionally adjusted for smoking, family history, and years of education. In the 'Confounding Assessment Analysis #2,' we also adjusted for body mass index (BMI) and physical activity. In the 'Interaction Assessment Analysis,' we stratified on aspirin use and repeated the latter analysis. RESULTS: The prevalence of current NANSAID and aspirin use was higher in our controls than in electronic database studies, consistent with the fact that non-prescription NANSAIDs accounted for 81% of all NANSAID use. Education, physical activity, and BMI also were associated with prescription NANSAID use. When each potential source of bias was removed, the OR for NANSAIDs moved further from 1.0 (i.e., toward a protective association with MI): 'Replicating Electronic Database' analysis (OR 1.00, 95% confidence interval [CI]: 0.78--1.28); 'Misclassification Assessment Analysis' (OR 0.89, 95%CI: 0.70--1.14); 'Confounding Assessment Analysis #1' (OR 0.85, 95%CI: 0.66--1.10); 'Confounding Assessment Analysis #2' (OR 0.78, 95%CI: 0.60--1.01); 'Interaction Assessment Analysis' (OR 0.69, 95%CI: 0.51--0.95). CONCLUSIONS: Limitations in electronic databases may be responsible for the lack of association of NANSAIDs on lower MI risk noted in these studies. Further studies-preferably randomized trials-are needed to address the risk-benefit ratio of NANSAID use.

Adult↗
PubMed2005

Practical aspects of sharing controls between case-control studies.

PURPOSE: We discuss the practical advantages and challenges of sharing controls among two or more concurrently conducted case-control studies. METHODS: We conducted two case-control studies, one of breast cancer and the other of endometrial cancer, with overlapping, shared control groups. The studies had overlapping geographic areas, identical telephone questionnaires and biosample collection, and identical age and race eligibility. RESULTS: Sharing controls reduced the number of potential controls that had to be identified by random-digit dialing by 25% and the number of eligible controls that had to be interviewed by 32%. The cost savings were approximately 2,96,000 dollars, or 7% of the program project that funded the studies. CONCLUSIONS: The disadvantage of sharing controls was the complexity of the design and the additional investigator time required to plan, monitor, and adjust the design. In the situation presented here, the complexities would have been reduced greatly if we had not attempted to frequency match on age in both studies. Generally, sharing controls is likely to work well when strict frequency matching is not required and there is a large overlap of interview questions, other data to be collected, and eligibility criteria among the studies.

Aged↗
PubMed2005

Choice of exposure scores for categorical regression in meta-analysis: a case study of a common problem.

OBJECTIVE: Reporting categorical relative risk estimates for a series of exposure levels versus a common reference category is a widespread practice. In meta-analysis, categorical regression estimates a dose-response trend from such results. This method requires the assignment of a single score to each exposure category. We examined how closely meta-analytical categorical regression approximates the results of analysis based on the individual-level continuous exposure. METHODS: The analysis included five studies on tea intake and outcomes related to colorectal cancer. In addition, we derived categorical mean and median values from published distributions of tea consumption in similar populations to assign scores to the categories of tea intake when possible. We examined whether these derived mean and median values well approximate the individual-level results. RESULTS: In meta-analytical categorical regression, using the midrange scores approximated the individual-level continuous analyses reasonably well, if the value assigned to the uppermost, open-ended category was at least as high as the lower bound plus the width of the second-highest category. Categorical mean values derived from the published distributions of regular tea (in the US) and green tea (in Japan) well approximated the slope obtained from individual-level analysis. CONCLUSION: Publication of both the categorical and the continuous estimates of effect in primary studies, with their standard errors, can enhance the quality of meta-analysis, as well as providing intrinsically valuable information on dose-response.

Age Distribution↗