Randomised controlled phase III trials that investigated first-line chemotherapy in patients with advanced stage IIIB and/or stage IV NSCLC were eligible for inclusion. Eligible interventions were standard chemotherapy defined as a platinum-containing doublet or a non-platinum doublet with newer agents (as defined in 2003 ASCO recommendations) that were regimens of platinum plus vindesine, etoposide or teniposide. Trials that evaluated three or more treatments had only the two arms that met the inclusion criteria included in the analyses. Trials had to evaluate treatment efficacy and patient quality of life to be eligible for the review. Trials of elderly populations (over 70 years) or patients with performance status two were excluded.
The included studies evaluated docetaxel, gemcitabine, paclitaxel, cisplatin, carboplatin and vinorelbine given in various combinations both as intervention and control arms. Doses were consistent with standard practice, apart from one trial that used 24-hour infusional paclitaxel. Quality of life was assessed using different instruments including EORTC QLQ C30, EuroQoL, FACT-L, LC13, LCSS, and QLQ Japan. Assessments were made at different time points across the trials, which ranged from every treatment cycle to every three or six weeks up to 26 weeks. Between 49% and 95% of patients completed the baseline quality of life questionnaire. The analysis methods varied between studies: some analysed outcomes at a specific time point (from six weeks from starting to 12 weeks after completing treatment); others used change from baseline or actual score at each assessment; some created a new variable indicating if patients had got worse, remained stable or improved.
Two reviewers independently performed the database searches and study inclusion was decided during a consensus meeting.