A 3-step intervention to improve adherence to cervical cancer screening: The SCAN randomized controlled trial

Abstract

The aim of this study was to test the effectiveness of a stepwise intervention with an increasing level of complexity and cost to increase adherence to organized cervical cancer screening. This was a randomized (1: 1) controlled trial, conducted among 13 Portuguese primary health care units. Participants (n = 1220) were women aged 25–49 years, eligible for cervical cancer screening, with a mobile phone number available. The tested intervention was a 3-step invitation to screening, based on automated text messages/phone calls (step 1), manual phone calls (step 2) and face-to-face interviews (step 3), applied sequentially to non-adherent women after each step. Participants in the control group were invited through a written letter (standard of care). The primary outcome was the proportion of women screened, which was assessed after step 1 (45 days after the initial invitation), steps 1 + 2 (90 days after the initial invitation) and steps 1 + 2 + 3 (150 days after the initial invitation). Adherence to cervical cancer screening was significantly higher among women assigned to the intervention than those in the control group for step 1 (39.9% vs. 25.7%, p < 0.001), steps 1 + 2 (48.6% vs. 30.7%, p < 0.001) and steps 1 + 2 + 3 (51.2% vs. 34.0%, p < 0.001). In conclusion, adherence to cervical cancer screening was higher by 17% among women invited through the 3-step intervention, compared to those receiving the standard invitation letter. The former strategy has the potential to be broadly implemented due to the low requirements of technology and training.