Studies were eligible if they reported tumour response and tolerability using the FG combination in colorectal cancer patients and were undertaken as phase I or II trials. Narrative or retrospective reviews, case-control reports and studies that described predictors of response or pharmacokinetics were excluded.
The intervention for phase I studies comprised a weekly maximum tolerated dose of gemcitabine between 900 to 1,000mg/m2 with either bolus 5-FU 450mg/m2 plus folinic acid 100mg/m2 or capecitabine 1,660mg/m2/day for three weeks with one week off. The intervention for phase II studies comprised a weekly, or bi-weekly, dose of gemcitabine between 750 and 1,250mg/m2 with continuous infusion 5-FU 200mg/m2 or bolus 5-FU 450mg/m2 plus folinic acid 100mg/m2 or capecitabine 2,500mg/m2/day.
The authors stated neither how the papers were selected for the review nor how many reviewers performed the selection.