Table 3

Risk differences for the dichotomous outcomes: informed choice, knowledge, positive attitudes/values towards screening, undecided and intention to be screened

OutcomeStudyGroupAssessedn (%)Difference, p value*
Informed choice†Mathieu et al 24Intervention11265 (58.0%)21.5%, p<0.001
Control19270 (36.5%)
Hersch et al 11§Intervention40999 (24.2%)8.8%, p=0.0017
Control40863 (15.4%)
KnowledgeMathieu et al 24Intervention113106 (93.8%)10.7%, p=0.01
Control189157 (83.1%)
Hersch et al 11**Intervention419122 (29.1%)13.0%, p<0.001
Control41971 (16.9%)
Positive attitudes††Mathieu et al 24 Intervention11188 (79.3%)0.2%, p=0.89
Control182144 (79.1%)
Hersch et al 11 Intervention409282 (68.9%)−14.4%, p<0.001
Control408340 (83.3%)
UndecidedMathieu et al 24 Intervention11721 (17.9%)−21.3%, p<0.001
Control20982 (39.2%)
Hersch et al 11 Intervention41969 (16.5%)9.3%, p<0.001
Control41930 (7.2%)
Intention to be screenedMathieu et al 24 Intervention11750 (42.7%)3.0%, p=0.64
Control20983 (39.7%)
Eden et al 25 Before7554 (72.0%)6.7%‡‡, p=0.123
After7559 (78.7%)‡‡
Gummersbach et al 20 Intervention178145 (81.5%)−7.1%, p=0.06
Control175155 (88.6%)
Hersch et al 11 Intervention419308 (73.5%)−13.1%, p<0.001
Control419363 (86.6%)
  • *Fisher’s exact test.

  • †Eden provided only a postintervention mean of the preparation for decision-making scale of 73.2 (18.1).

  • ‡Out of the women assessed, including undecided women in the denominator.

  • §Informed choice defined as adequate knowledge and intentions consistent with attitudes.

  • ¶Knowledge (according to Mathieu): score higher than 5 out of 10.

  • **Knowledge (according to Hersch): adequate knowledge when scoring at least 50% of the total available marks, including at least one numerical mark, on all three screening outcome subscales (breast cancer mortality benefit, false-positive screening result and overdiagnosis).

  • ††Positive attitudes/values >50 out of 100 according to Mathieu and ≥24 out of 30 according to Hersch.

  • ‡‡Difference as postintervention minus preintervention values.