Table 4.

ORs and 95% CIs of participating in screening after randomized intervention

Sample size (no.)Participated in screening
95% CI for proportion
Univariate modeling
Multivariate modelinga
No.%Differenceb95% CIOR95% CIOR95% CI
First intervention
    Modified invitation6065163827.01.3−0.3 to 2.91.11.0–1.21.00.9–1.1
    Usual invitation6092156625.70.0(Reference)1.0(Reference)1.0(Reference)
Second interventionc
    Written reminder447669315.59.27.9–10.52.72.4–3.22.92.5–3.3
    No written reminder44772826.30.0(Reference)1.0(Reference)1.0(Reference)
Third interventionc
    Phone reminder62826041.431.426.9–35.96.34.7–8.56.95.0–9.4
    No phone reminder6686710.00.0(Reference)1.0(Reference)1.0(Reference)
  • a Controlling for experimental condition and for all background factors included in Tables 1 and 2.

  • b Difference in proportion of attenders in comparison with reference categories.

  • c Because no washout period existed between the interventions, displacement in attendance might be expected.