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Background: Cervical cancer is the most common cancer among women in developing countries and is the leading cause of cancer death in Indian women.Since cytology-based screening is not easily implementable in India,there is a need to evolve simpler alternatives.Methods: We initiated a cluster-randomized controlled trial in 1998 to investigate the efficacy of VIA screening by primary health workers(PHWs)in reducing cervical cancer mortality.Women aged 35-64 years with no prior history of cancer were included.The study was designed to include 20 clusters with an average of 7,500 eligible women per cluster.Four rounds of cancer education and VIA screening were conducted by PHWs at 24-month intervals in the screening group,while cancer education was offered once at recruitment to the control group.Recruitment was completed in March 31,2002.Although the study was planned for 16 years,we analysed the results on the advice of the DSMC at 12 years.Results: We recruited 75,360 women from 10 clusters in the screening group and 76,178 women from 10 comparable clusters in the control group.The analysis is on an intention-to-treat basis.In the screening group,we achieved 89%participation for screening and 79%compliance for post-screening diagnostic confirmation.The quality of screening by PHWs was comparable to that of an expert gynecologist(κ=0.84).The incidence of invasive cervical cancer was 26.74 per 100,000(95%CI: 23.41-30.74)in the screening group and 27.49 per 100,000(95%CI: 23.66-32.09)in the control group.Compliance to treatment for invasive cancer was 86.34%in screening group and 72.29%in the control group.The screening group showed a 31%reduction in cervical cancer mortality(mortality rate ratio RR=0.69; 95%CI: 0.54-0.88; p=0.003)compared to the control group.A 7%reduction was also observed in all-cause mortality(mortality rate ratio RR=0.93; 95%CI: 0.79–1.10; p=0.41).Conclusions: VIA screening conducted by PHWs significantly reduced cervical cancer mortality.VIA screening is easily implementable and could prevent 22,000 cervical cancer deaths in India and 72,600 deaths in resource poor countries annually.