Inverse-variance weighted averages of study-specific log IRRs can also be achieved by using a suitably specified Poisson regression model [ 4, 5].
This approach, sometimes referred to as the "naive method" [ 16, 17], estimates a pooled effect size that is the ratio of exposure time-weighted averages of study-specific rates in the intervention and control arms.
The overall average of study quality was 2.375.
Average monthly income of SAR 93,472/year, rounded to SAR 8000/month ($2133) in Saudi Arabia was also used, which was quite close to monthly income average of study population [ 45].
We pooled estimates by random-effects meta-analysis according to the method of DerSimonian and Laird and fixed-effect meta-analysis by calculating the weighted average of study estimates with the inverse of estimates variance used as the study weight.
In the current example the pooled curve with treatment A was based on the average of study specific nuisance parameters for scale and shape of all treatment A (i.e. DTIC) controlled trials.
A fixed-effect model was used to provide a fair weighted average of studies.
* Likelihood used in model base case is the weighted average of studies reviewed where the numerator and denominator across multiple studies were summed.
The association between risk of lung cancer and family history of the disease was derived as a weighted average of study-specific estimates of the RR, using inverse variance weights (Kleinbaum et al, 1982).
Based on an approximate diabetes prevalence of 10% (as an average of studies discussed earlier), it is estimated that approximately 350,000 patients are not specifically covered for payment of diabetes treatment.
The average number of participants was 402, the average cost per participant was approximately £2500, and the average number of study centres was 16.
