Table 3

Exploration of the predicted probability, sensitivity, specificity, AuROC, PPV and NPV of selected individual and combined DAP items

DescriptionPredicted probability of pregnancy at DAP scoreEmpirical cut-pointSensitivitySpecificityAuROCPPVNPVDomains coveredPositive and negatively worded items
04
Total DAP:
All 14 items
79.4%0.9%1.9678.0%81.0%0.8543.0%95.0%AllYes
Single DAP item:
Pregnant: good thing for me.
66.7%2.1%2.568.1%86.3%0.7749.0%93.3%1Positive only
Single DAP item:
Baby: end of the world for me.
27.4%0.565.3%77.7%0.7236.2%92.0%1Negative only
Two DAP items:
Pregnant: good thing for me and Baby: end of the world for me.
71%0.7%1.2565.3%90.1%0.7856.0%93.1%1Yes
Three DAP items: Pregnant: good thing for me, Pregnant: excited, Baby: hard to achieve other things.83%2.8%2.1562.5%87.1%0.7548.4%92.3%AllYes
Three DAP items: Pregnant: good thing for me, Pregnant: excited, Baby: end of the world for me.73%1.2%1.4966.7%87.4%0.7750.5%93.1%1, 2Yes
Three DAP items: Pregnant: good thing for me, Baby: end of the world for me, Baby: makes me smile.68%1.0%1.4969.4%84.4%0.7746.3%93.5%1, 2Yes
Three DAP items: Pregnant: good thing for me, Baby: want, Baby: end of the world for me.72%13.9%1.4966.7%90.3%0.7957.1%93.3%1Yes
Three DAP items: Pregnant: good thing for me, Baby: end of the world for me, Baby: hard for me to manage.76%8.8%1.8275.0%77.2%0.7638.8%94.1%1, 3Yes
Four DAP items:
Pregnant: good thing for me, Pregnant: excited, Baby: want, Baby: end of the world for me.
73%1.4%1.6366.7%89.2%0.7854.5%93.2%1, 2Yes
Four DAP items:
Pregnant: good thing for me, Pregnant: excited, Baby: end of the world for me, Baby: hard to achieve other things.
81%1.2%1.8866.7%83.9%0.7544.4%92.9%AllYes
Six DAP items:
Pregnant: wouldn't mind, Pregnant: unhappy, Baby: want, Baby: positive addition to life, Baby: makes me smile, Baby: hard for me to manage.
73%1.6%1.9375.0%80.9%0.7843.2%94.4%AllYes
  • AUROC, area under the receiver operating curve; DAP, Desire to Avoid Pregnancy; NPV, negative predictive value; PPV, positive predictive value .