Study designs of evaluations included in the review
The review included individual patient data (IPD) from randomised controlled trials (RCTs) with concealed allocation to treatment group, which were conducted between 1 January 1965 and 31 December 1993.
Specific interventions included in the review
Studies of any of the following interventions were eligible for inclusion:
locoregional treatment plus chemotherapy compared with locoregional treatment alone;
neoadjuvant chemotherapy plus radiotherapy compared with concomitant or alternating radiochemotherapy;
radical surgery plus radiotherapy compared with neoadjuvant chemotherapy plus radiotherapy in responders, or radical surgery and radiotherapy in nonresponders.
The trials included under the first criteria used four different types of chemotherapy: platin and fluorouracil; polychemotherapy with platin; polychemotherapy without platin; and monochemotherapy. The timing of this therapy was adjuvant, neoadjuvant or concomitant.
Participants included in the review
Previously untreated patients with non-metastatic head and neck squamous-cell carcinoma (tumours of the oral cavity, oropharynx, hypopharynx and larynx) were eligible for inclusion. Patients who had been treated for another cancer, or who had nasopharyngeal carcinomas, were excluded.
Outcomes assessed in the review
The inclusion criteria for the outcomes were not specified. The primary outcome of interest was overall survival. For the review question on larynx preservation, a secondary outcome of disease-free survival was also assessed. This took local or distant recurrence, a secondary primary and death into account.
How were decisions on the relevance of primary studies made?
The authors did not explicitly state how decisions on the relevance of the studies were made.