Subgroup effects despite homogeneous heterogeneity test results
نویسندگان
چکیده
BACKGROUND Statistical tests of heterogeneity are very popular in meta-analyses, as heterogeneity might indicate subgroup effects. Lack of demonstrable statistical heterogeneity, however, might obscure clinical heterogeneity, meaning clinically relevant subgroup effects. METHODS A qualitative, visual method to explore the potential for subgroup effects was provided by a modification of the forest plot, i.e., adding a vertical axis indicating the proportion of a subgroup variable in the individual trials. Such a plot was used to assess the potential for clinically relevant subgroup effects and was illustrated by a clinical example on the effects of antibiotics in children with acute otitis media. RESULTS Statistical tests did not indicate heterogeneity in the meta-analysis on the effects of amoxicillin on acute otitis media (Q = 3.29, p = 0.51; I2 = 0%; T2 = 0). Nevertheless, in a modified forest plot, in which the individual trials were ordered by the proportion of children with bilateral otitis, a clear relation between bilaterality and treatment effects was observed (which was also found in an individual patient data meta-analysis of the included trials: p-value for interaction 0.021). CONCLUSIONS A modification of the forest plot, by including an additional (vertical) axis indicating the proportion of a certain subgroup variable, is a qualitative, visual, and easy-to-interpret method to explore potential subgroup effects in studies included in meta-analyses.
منابع مشابه
Author ' s response to reviews Title : Subgroup effects despite homogeneous heterogeneity test results
متن کامل
Modeling Heterogeneity in Phase II Clinical Trials
Problem statement: The common assumption in non-randomized Phase II clinical trials is a homogeneous population with homogeneous response. This assumption is at odds with many trials today; a heterogeneous response due to the existence of subgroups. Approach: In order to examine the effects of heterogeneity on the trial outcome, a systematic platform is developed to quantify the range and class...
متن کاملExperimental Study of Foam Flooding in Low Permeability Sandstones: Effects of Rock Permeability and Microscopic Heterogeneity
Foam flooding (or injection of foam) is a common technology to enhance oil recovery. Although the effects of permeability on foam flooding were well studied in many laboratory experiments, little research has been focused on the specificity of low permeability. In this paper, a series of constant-quality nitrogen foam flow experiments were conducted to investigate the effects of permeability on...
متن کاملInvestigating the Effects of Heterogeneity, Injection Rate, and Water Influx on GAGD EOR in Naturally Fractured Reservoirs
The gas-assisted gravity drainage (GAGD) process is designed and practiced based on gravity drainage idea and uses the advantage of density difference between injected CO2 and reservoir oil. In this work, one of Iran western oilfields was selected as a case study and a sector model was simulated based on its rock and fluid properties. The pressure of CO2 gas injection was close to the MMP of th...
متن کاملWhat Stimulates Teams to Engage in Learning Behavior? the Influence of Demographic Heterogeneity, Subgroup Salience, and Context
This paper examines team learning behavior; a set of complementary actions that teams engage in to improve their outcomes. We theorize about the impetus that is subsistent within a number of designfactors, both internal and external to the team. Regarding a team’s composition, we investigate the potentially concurrent effects of demographic heterogeneity and subgroup salience. Models using data...
متن کاملذخیره در منابع من
با ذخیره ی این منبع در منابع من، دسترسی به آن را برای استفاده های بعدی آسان تر کنید
عنوان ژورنال:
دوره 10 شماره
صفحات -
تاریخ انتشار 2010