Assessment of outcomes is essential in order to improve available palliative treatments. Collecting follow-up information can be a challenging task in the palliative setting. We compared the effectiveness of data collection by telephone contact and clinic visit in 112 patients with brain metastases treated with whole-brain radiotherapy. The first 56 patients (group A) were followed by telephone only. The second 56 patients (group B) were asked to attend an outpatient clinic appointment 4 weeks after radiotherapy. Successful contact was defined as obtaining data at week 4. Patients in the two groups did not differ significantly with regard to age, sex, performance status, primary site, number of brain metastases, or the treatment given. The proportions of patients with successful follow-up contact at week 4 were 45% and 61% in groups A and B, respectively ( P = 0.09). The quality of the collected data did not differ significantly between the two groups. The side effects and responses to therapy were similar. However, there were significantly more patients with a reduced dose of dexamethasone among the successful contacts in group B, which probably reflected the better condition of the patients coming back to clinic at week 4. In conclusion, there was a trend towards more successful data collection in our clinic follow-up. Some of the observed outcome data suggest that the two methods of follow-up might be reaching different populations of patients; considering this and the high attrition rate, a combined follow-up strategy of clinic and telephone contacts might be the best strategy.