Background Organisational barriers to primary healthcare are still relevant in developing countries. Although descriptive reports of some experiences focusing on improving accessibility have been published, few studies have evaluated specific interventions aimed at overcoming the organisational obstacles.

Objective To evaluate the results of a project designed to improve accessibility to healthcare services in Salvador, Bahia, Brazil.

Methodology An evaluative, cross-sectional, ex post facto study that included a control group was carried out in a random sample of 710 users of 25 healthcare units of the primary municipal healthcare network. The association between the project implementation degree and outcome variables was measured by prevalence ratios (PR) and statistical inference was based on Taylor series 95% CIs.

Results Better access to primary healthcare was found in units in which the intervention had been implemented than in those in which it had not been implemented, particularly with respect to reducing avoidable queues, the waiting time for scheduling a consultation (PR=0.23; 95% CI 0.15 to 0.34); the time of arrival in the queue (PR=0.16; 95% CI 0.09 to 0.31) and the introduction of a system for scheduling appointments by telephone (PR=0.76; 95% CI 0.70 to 0.83).

Conclusion Owing to the simplicity of the programme and the impact it achieved, it may be reproduced in other underdeveloped countries to improve access to healthcare services. In addition, some of the instruments may be used in routine programme evaluation.