Across strata, both cases and controls are independent, but not necessarily identically distributed.
The area around the residences of the index case-patients was divided into 3 strata: strata 1 and 2 (within 200 m of each case-patient) and stratum 3 (201–1,000 m).
Fourth, to assess the impact of choice of time strata, we analysed the data using 14 day (rather than calendar month) time strata to define case and control days.
The probability distributions used for the input parameters were triangular for the annual PAMV volume and log-normal for the LOS estimates in each of the strata; in the case of the latter log-normal was used as the best fit for non-parametric data.
Cases and controls are classified into strata, for example by a score based on the first few principal components in a genome-wide study [ 6].
Instead, generally the spread in error densities seem either restricted to low strata values in the case of elevation, slope, and relative elevation, or are more widespread across the strata values in the case of cloudiness, mean annual precipitation, and dry season length.
2 Only those strata with at least case and one control having non-missing values were included to logistic regression analyses.
Seaside towns are built on strata upon strata of happy memories; a sort of emotional geology.
An initial Cox proportional hazards model based on all five trials (797 patients, 20/797 cases dropped) was generated with time to healing (days) as the dependent variable, healing as the event, study centres as strata, and bandage type as the only covariate.
By strata, 94.0% of the cases in Strata 1, 86.3% of the cases in Strata 2, and 94.9% of the cases in Strata 3 were reviewed from the target sample.
