Analysis of Cohort Data (Kenya PNC) Unintended Pregnancy Weiwei Zhou, Isolde Birdthistle, Susannah Mayhew - on behalf of the Integra Team

Cohort datasets Cohort: Kenya PNC (n=869) Four rounds: Baseline, 6 months, 16 months, 24 months Study group: Intervention, Comparison Facility: 6 (Intervention) + 6 (Comparison) UID: Facility code + Interviewers’ code + Client No. Question: Does integration affect the incidence of unintended pregnancy? Method: Time to event (survival) analysis

Outcome: Event (unintended pregnancy) Event occurred Y = 1 Since the last time we saw you (x months ago), have you become pregnant? 1.Yes 2.No 3.Missing At the time you became pregnant with the last pregnancy, did you: 1.Want to become pregnant then; 2.Want to wait until later; 3.Not want to have any/more children? 4.Missing + (AND) =

Event did not occur Y = 0 Since the last time we saw you (x months ago), have you become pregnant? 1.Yes 2.No 3.Missing At the time you became pregnant with the last pregnancy, did you: 1.Want to become pregnant then; 2.Want to wait until later; 3.Not want to have any/more children? = + (AND) Outcome: Event (unintended pregnancy)

If Y = missing, Y is considered as 1 What did you do when you discovered that you were pregnant with your last pregnancy? 1.Nothing 2.Attempted to stop but not succeed, 3.Attempted to stop and succeed. OR = How did you feel when you discovered you were pregnant with your last pregnancy? 1.Happy 2.Unhappy/disappointed 3.Felt nothing 4.other Were you using a family planning method when you became pregnant with this last pregnancy? 1.Yes 2.No AND Outcome: Event (unintended pregnancy)

Date of unintended pregnancy How many months pregnant are you? = xx months Miscarried /aborted Given birth OR R(x-1) interview date R(x) interview date xx months R(x-1) interview date ( b – a )/2 R(x) interview date ba R(x-1) interview date R(x) interview date 9 months

BaselineRound 1Round 2Round 3 Time (from baseline interview date to event date)

1) Study Group (Intervention and Comparison) 2) Baseline index (categorical, =1.5) 3) Averaged cumulative index (per day). Exposure

Exposure: cumulative index Blue circle: Event (size of circle=level of integration) Red/Green dot: Higher/Lower ACI exposure group

Analysis plan Cox proportional hazards model Univariate analysis Multivariable analysis, Adjusted for: Demographic: age, education, religion, employment statutes, household income SES Fertility preference: number of children, desired additional number of children, want/when to have another child, also husband’s wish. Other: HIV status, any children died, numbers of pregnancies Test of model assumption

Univariate and multivariable analysis, PNC Kenya Univariate Adjusted nHRP-value HRP-value Design study group Comparison306Ref Intervention (0.38, 1.06) (0.32, 1.20)0.153 Baseline index <1.5368Ref >= (0.83, 5.00) (0.51, 4.15)0.488 Cumulative index Lower432Ref Higher (0.69, 1.78) (0.46, 1.50)0.549

Kaplan-Meier plot, PNC Kenya

Limitations and Conclusions Index of visits to non-study clinics are not available. Mean index values of study clinics have been used. Event doesn't have an uniform distribution, thus the averaged cumulative index may not represent daily/monthly exposure to clinics. Interaction terms Kenya PNC: No significant effect by using study group, baseline index, or cumulative index as exposure variable.