Effect of prepare Intervention on sexual initiation and con - PowerPoint Presentation

Slide1

Effect of prepare Intervention on sexual initiation and condom use among adolescents in Dar es Salaam: Preliminary analysisSlide2

AIMDar PREPARE Intervention aimed at examining the effect of the Intervention on;1. Delaying sexual debut(Incidence of sexual debut/ action planning to delay sex)2. Practice of safer sexual behavior (Use of condom during last sex/Action plan to use condom)Slide3

School selection and allocation38 schools randomly selected t represent urban and semi-urban Dar es salaamMatched by size and locationAllocated to the two arms (19 Intervention and 19 control schools )Slide4

Study DesignControlInterventionF1

F1

F2

F2

Intervention

Booster

6 months

6 months

12 monthsSlide5

AnalysisCompare baseline socio-demographic and outcome scales by intervention statusExamine and test best correlation structure for repeated measures ( use QIC)Examine change in mean scores overtime using extended generalized estimating equation modeling (xtgee)for repeated measures (Use QIC)Slide6

Use of GEE (xtgee)Repeated measures are positively correlatedCorrelation decrease by measurement occasionGEE- form of Generalized Linear Mixed ModelExcellent for balanced designChange in link function accommodate Count (Poisson) or Binary (binomial) outcomeHandle more then two measurement occasions

Control for correlation Slide7

Schematic diagram of follow up rateBaseline

5091

Months 6 (F1)

4783

Months 12 (F2)

4370

308 lost (6.0%)

413 lost (8.6%)Slide8

Baseline comparisonA total 5091 participants in baselineParticipants from control schools were significantly older than those from intervention school (12.39 versus 12.43; p=0.020)More from standard 6 (64.1% versus 61.8%; p=0.025)All other variables comparable (except HAVES, communication with friends and parents)Slide9

Variable InterventionControl

Mean difference

P-value

Action plan condom use

2.598

2.578

0.0198

0.4743

Action plan delayed sex

2.809

2.793

0.1529

0.6163

Self-efficacy Communicate with peer

2.266

2.225

0.0407

0.0678

Peer communication

1.646

1.606

0.03944

0.0946

Communication with friends

1.384

1.338

0.0465

0.0007

Communication with parents

1.338

1.305

0.0335

0.0328

Self-efficacy to delay sex

2.591

2.596

0.0046

0.8614

Self-efficacy to use Condom

2.439

2.479

0.0396

0.0930

Social norms condom use

3.352

3.407

0.0549

0.0518

Social norm delay sex

3.516

3.487

0.0297

0.2780Attitude delay sex (negative)2.3212.2970.02390.3343Attitude delay sex (positive)3.4333.4330.00020.9936Puberty knowledge1.5041.5030.00050.9445Myth about condom 2.2312.2440.01270.4939Haves 3.7713.992-0.22080.0003

Baseline mean scale comparison between Intervention and control schoolsSlide10

Sexual activity and initiationSignificantly large proportion of intervention group participants were sexually active (10.7% Intervention vs 8.9% control, p=0.026)Slide11

Incidence of sexual debut among female adolescent by intervention statusFemaleMonth 6

Month 12

InterventionN=1052 at risk

Control

N=1113 at risk

60 new initiation

Incidence 11/100 PYAR

52 new initiation

Incidence 9.0/100PYAR

75 new initiation

Incidence 7/100PYAR

114 new initiation

Incidence 9.7/100PYAR

RR =1.6, p=0.024

*Assumption: Debut occurred mid follow timeSlide12

Incidence of sexual debut among male adolescent by intervention statusMaleMonth 6

Month 12

InterventionN=1158 at risk

Control

N=1213 at risk

65 new initiation

Incidence 10.9/100 PYAR

78 new initiation

Incidence 12.4/100PYAR

87 new initiation

Incidence 7.2/100PYAR

126 new initiation

Incidence 10.0/100PYAR

RR =1.9, p<0.001

*Assumption: Debut occurred mid follow timeSlide13

Change over time in mean scales for action plan to delay sexSlide14

Change over time in mean scales for action plan to use condomSlide15

Correlation and covariate structure pwcorr sex0 sex1 sex3 | sex0 sex1 sex3 sex0 | 1.0000 sex1 | 0.7000 1.0000 sex3 | 0.5791 0.8272 1.0000 corr sex0 sex1 sex3, cov | sex0 sex1 sex3 -------------+--------------------------- sex0 | .088426 sex1 | .080242 .148585 sex3 | .074042 .137103 .184882Slide16

Intervention effect on the mean score : Female 

INTERVENTION

CONTROL

Variable

Occasion

Coefficient

P-value

Coefficient

P-value

Action to delay sex

baseline

ref

ref

ref

ref

Month 6

0.0469

0.256

0.0526

0.237

Month 12

0.1055

0.033

0.0686

0.144

Group

0.1345

0.015

Action to use condom

baseline

ref

ref

ref

ref

Month 6

0.172

<0.001

0.1916

<0.001

Month 12

0.143

0.001

0.1857

<0.001

Group

0.0174

0.678

Sexual initiation

baseline

ref

ref

ref

ref

Month 6

0.0746

<0.001

0.0694

<0.001

Month 12

0.148

<0.001

0.1318

<0.001

Group

0.1361

0.009

Condom use

baseline

ref

ref

ref

ref

Month 6

0.1727

<0.001

0.2660

<0.001

Month 12

0.2910

<0.001

0.3070

0.001

Group

0.0162

0.463Slide17

Intervention effect on the mean score : Male  

INTERVENTION

CONTROL

Variable

Occasion

Coefficient

P-value

Coefficient

P-value

Action to delay sex

baseline

ref

ref

ref

ref

Month 6

0.0839

0.004

0.1049

<0.001

Month 12

0.1497

<0.001

0.1562

<0.001

Group

0.003

0.633

Action to use condom

baseline

ref

ref

ref

ref

Month 6

0.0729

0.048

0.0546

0.173

Month 12

0.1880

0.0190.09260.033 Group0.07400.0876     Sexual initiationbaselinerefrefrefref Month 60.06560.0100.02720.530 Month 120.1249

0.007

0.0092

0.843 

Group

0.1126

0.043

Condom use

baseline

ref

ref

ref

ref

Month 6

0.3209

<0.001

0.1484

0.025

Month 12

0.3694

<0.001

0.2672

<0.001

Group

0.2173

0.004Slide18

ConclusionsThe intervention was effective in;Promoting action plan to delay sex for both sexdelaying sexual initiation for both male and female adolescentsCondom use among male but not among womenSlide19

Further analysisExamine intervention effectiveness in promoting other aspect of safer sex-multiple sexual partnersEffective on communication, self efficacy etcPredictors of observed positive outcomes