Finding the minimal intervention needed for sustained mammography adherence.

Background: Regular adherence to mammography screening saves lives, yet few women receive regular mammograms.

Design: RCT.

Setting/participants: Participants were recruited through a state employee health plan. All were women aged 40-75 years and had recent mammograms prior to enrollment (n=3547). Data were collected from 2004 to 2009.

Intervention: Trial tested efficacy of a two-step adaptively-designed intervention to increase mammography adherence over 4 years. The first intervention step consisted of three reminder types: enhanced usual care reminders (EUCR); enhanced letter reminders (ELR); both delivered by mail, and automated telephone reminders (ATR). After delivery of reminders, women who became off-schedule in any of the 4 years received a second step of supplemental interventions. Three supplemental intervention arms contained priming letters and telephone counseling: barriers only (BarriCall); barriers plus positive consequences of getting mammograms (BarriConCall+); and barriers plus negative consequences of not getting mammograms (BarriConCall-).

Main Outcome Measures: Average cumulative number of days non-adherent to mammography over 4 years based on annual screening guidelines (analyses conducted in 2009).

Results: All reminders performed equally well in reducing number of days of non-adherence. Women randomized to receive supplemental interventions had significantly fewer days of non-adherence compared to women who received EUCR (p=0.0003). BarrConCall+ and BarrConCall- conditions did not significantly differ in days non-adherent compared to women in the barriers-only condition (BarriCon).

Conclusions: The minimal intervention needed for sustained mammography use is a combination of a reminder followed by a priming letter and barrier-specific telephone counseling for women who become off-schedule. Additional costs associated with supplemental interventions should be considered by organizations deciding which interventions to use.

Trial Registration Number: NCT01148875.