# Protocolo de estudo experimental
# Técnica de amostragem multi etápica
Abstract
Introduction Screening is highly effective for cervical
cancer prevention and control. Population-based screening
programmes are widely implemented in high-income
countries, although adherence is often low. In Portugal,
just over half of the women adhere to cervical cancer
screening, contributing for greater mortality rates than in
other European countries. The most effective adherence
raising strategies are based on patient reminders, small/
mass media and face-to-face educational programmes,
but sequential interventions targeting the general
population have seldom been evaluated. The aim of
this study is to assess the effectiveness of a stepwise
approach, with increasing complexity and cost, to improve
adherence to organised cervical cancer screening: step
1a—customised text message invitation; step 1b—
customised automated phone call invitation; step 2—
secretary phone call; step 3—family health professional
phone call and face-to-face appointment.
Methods A population-based randomised controlled
trial will be implemented in Portuguese urban and rural
areas. Women eligible for cervical cancer screening will
be randomised (1:1) to intervention and control. In the
intervention group, women will be invited for screening
through text messages, automated phone calls, manual
phone calls and health professional appointments, to
be applied sequentially to participants remaining nonadherent
after each step. Control will be the standard of
care (written letter). The primary outcome is the proportion
of women adherent to screening after step 1 or sequences
of steps from 1 to 3. The secondary outcomes are:
proportion of women screened after each step (1a, 2 and
3); proportion of text messages/phone calls delivered;
proportion of women previously screened in a private
health institution who change to organised screening. The
intervention and control groups will be compared based on
intention-to-treat and per-protocol analyses.
Ethics and dissemination The study was approved
by the Ethics Committee of the Northern Health Region
Administration and National Data Protection Committee.
Results will be disseminated through communications in
scientific meetings and peer-reviewed journals.