The distribution of the number of siRNA experiments per study is highly skewed in the siRecords collection. A. Studies were categorized based on the number of siRNA experiments reported. Only 6 out of the 1,417 studies (0.4%) reported > 30 siRNA experiments per study. B. The distribution of the total number of records in each category. Six hundred and fifty-seven records (representing 17.5% of the entire dataset) originated from the 6 studies with > 30 records per study.