Coding:

Coding,  the process by which the published papers in our sample were read, reviewed, and  documented, was done by C.C.W., W.D.B., J. W., and T.E.N. Articles used were  the result of a PubMed search over the past 10 years. At the onset, 1086 
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article required two separate ‘yes’ votes to be included in our study, and two  separate ‘no’ votes to be excluded. Disputes were resolved via group  discussion. 885 articles were included in our study of which 285 were randomly  sampled and divided evenly four ways. After full text screening, 182 articles were included. Animal  studies, follow-up studies of adult survivors of pediatric ALL, exclusively  genetic studies, and genome-wide association studies were excluded.  Meta-analyses were excluded to avoid redundancy, as we had already coded their  constituent studies individually. Studies combining original research with  meta-analysis were included so as to not exclude original research.  Each person was partnered with another so that all of the coding process was reviewed once over. The papers were analyzed for nine specific  pieces of information: outcome, measurement device, metric, method of  aggregation, primacy of outcome, whether the outcome was a harm or side effect  of an intervention, study design, sample size, & study type. An abstraction manual was formulated by D.H. to standardize the coding process.