Table 2.

Studies on improving oral contraceptive pills medication adherence among adolescents and young adults, by intervention (N = 15).

Year	Author	Sample size, sex, ages	Location	Study design	Intervention description	Control description	Primary outcome	Effectsa
Enhanced clinic-based or school-based counseling
2015	Minguez [26]	N = 2076 high school students; 908 women and 1168 men; 14–18 years old	USA	QS	Enhanced school-based services and decentralized OCP dispensing	SOC health services	Self-reported OCP use at 12 months	9th Graders: RR = 0.15 (95% CI: 0.02–1.46)10–12th Graders: RR = 3.25 (95% CI: 1.83–5.77)
2012	Berenson [29]	N = 1155 women, 16–24 years old	USA	RCT	Enhanced clinic-based counselingEnhanced clinic-based counseling and weekly phone calls	SOC counseling	OCP continuation at 12 months, measured via self-report, pill counts, and medical records	OR = 0.80 (95% CI: 0.63–1.40)OR = 1.09 (95% CI: 0.86–1.53)
2005	Wang [33]	N = 2227 women, 15–24 years	China	QS	Peer-based counseling sessions	SOC counseling	Self-reported OCP use at 20 months	OR = 0.75 (95% CI: 0.52–1.08)
2004	Gilliam [31]	N = 33 postpartum women, <25 years old	USA	RCT	SOC counseling and post-delivery OCP counseling	SOC counseling	Self-reported OCP continuation at 12 months	OR = 0.67 (95% CI: 0.11–3.99)
2004	Bender [93]	N = 160 women, <24 years	Iceland	RCT	Enhanced OCP counseling	SOC counseling	Self-reported OCP use at 6 months	OR = 1.08 (95% CI: 0.54–2.14)
1997	Kirby [28]	N = 354 7th grade students, 12–13 years old (sex breakdown not specified)	USA	CRCT	Enhanced school-based OCP counseling	SOC curriculum	Self-reported OCP use at last sex	OR = 0.57 (95% CI: 0.36–0.91)
1997	Kirby [34]	N = 10 600 middle school students, mean age 12.5 years old (sex breakdown and age range not specified)	USA	CRCT	Adult-led enhanced school-based OCP counselingPeer-led enhanced school-based OCP counseling	SOC curriculum	Self-reported OCP use at last sex	RR = 0.79 (95% CI: 0.46–1.35)RR = 0.78 (95% CI: 0.47–1.28)
1993	Hanna [27]	N = 51 women, 16–18 years old	USA	RCT	Enhanced clinic-based counseling	SOC counseling	Self-reported mean OCP adherence score at 3 months	10.24 in intervention versus 8.95 in control, ratio of 1.14, P = 0.05
1984	Jay [32]	N = 57 women, 15–19 years old	USA	RCT	Peer-based counseling	SOC nurse-led counseling	Mean OCP adherence score, measured as noncompliance at 4 months measured via urinary marker for OCP use	0.85 in intervention versus 1.06 in control; ratio of 0.80
Phone and web-based interventions
2012	Castaño [22]	N = 962 women, 13–25 years old	USA	RCT	Daily one-way and two-way text messages	SOC counseling	Self-reported OCP continuation at 6 months	OR = 1.44 (95% CI: 1.03–2.00)
1999	Chewning [30]	N = 949 women, <20 years old, mean age 17 (age range not specified)	USA	RCT	Enhanced OCP counseling via web-based application	SOC counseling	Self-reported OCP use	Chicago: 96.6% in intervention versus 91.2% in controlMadison: 98.8% in intervention versus 97.7% in control
							Self-reported mean number of months with OCP use	Chicago: 8.2 months in intervention versus 8.6 months in controlMadison: 9.4 months in intervention versus 9.5 months in control
Multi-month dispensing
2011	White [23]	N = 85 women, <18 years old (age range not specified)	USA	RCT	Increased number of pill packs (7 packs)	Standard 3 pill packs	Self-reported OCP continuation at 6 months	OR = 7.55 (95% CI: 2.38–23.95)
Same-day pill starts
2008	Edwards [24]	N = 539 women, 12–17 years old	USA	RCT	Same-day start of OCPs with DOT	Standard OCP start	Starting second pill pack	OR = 1.80 (95% CI: 1.10–3.30)
							Self-reported OCP continuation at 6 months	OR = 1.1 (95% CI: 0.70–1.80)
2007	Westhoff [25]	N = 1720 women, <25 years old	USA	RCT	Same-day start of OCPs with DOT	Standard OCP start	Starting second pill pack	OR = 1.5 (95% CI: 1.00–2.10)
							Self-reported OCP continuation at 6 months	OR = 1.1 (95% CI: 0.80–1.30)
Social marketing campaigns
2000	Van Rossem [94]	N = 868 women, 12–22 years old	Cameroon	QS	Social marketing and mass media campaign, youth clubs	SOC OCP provision	Self-reported OCP use preintervention and postintervention	15.0% Increase in OCP use in intervention setting versus 9.4% increase in control setting; χ2 = 0.96, P = 0.33

95% CI, 95% confidence interval; CRCT, cluster randomized controlled trial; DOT, directly observed therapy; OCP, oral contraceptive pills; OR, odds ratio; QS, quasi-experimental; RCT, randomized controlled trial; RR, relative risk; SOC, standard of care.

^aBold text denotes a statistically significant intervention effect.