From: Public health interventions in midwifery: a systematic review of systematic reviews
Author & Year | Number of papers included (date range) | Intervention | Primary outcome(s) and additional key public health outcomes of interest | Main Results /Findings | Meta Analysis |
---|---|---|---|---|---|
Antenatal | |||||
Screening | |||||
Bricker et al.[26] | 79 (1980-1998) | Routine USS in pregnancy | 1. Clinical effectiveness of USS (11) | 1. 2 stage regimen of USS in pregnancy recommended (early & around 20 weeks) | No |
 |  |  | 2. Cost effectiveness of USS (9) | 2. cost effectiveness results not reported on in this paper |  |
 |  |  | 3. Women’s views of USS (59 studies, 76 reports) | 3. USS is attractive to women. Findings of uncertain clinical significance may impact psychologically on women-further research needed. Anxiety reduction after USS is likely to reflect raised anxiety prior to scan than a real reduction |  |
Whitworth et al.[27] | 11 (1982-2009) | Routine USS in early pregnancy | Primary: detection of major fetal abnormality, detection of multiple pregnancy, Induction of labour for ’post-term’ pregnancy, perinatal death Multiple secondary outcomes | Reduces failure to detect multiple pregnancy (RR 0.07 95% CI 0.03-0.17) | Yes |
 |  |  |  | Reduction in IOL for post term (RR 0.59 95% CI 0.42-0.83) |  |
Sangkomkam-hang et al. [28] | 1 (2004) | Antenatal lower genital tract infection screening to prevent PTD | Primary: preterm birth | One trial (n=4155) was included. Preterm birth was significantly lower in the intervention group than in the control (RR 0.55 95% CI 0.41-0.75). | No |
 |  |  | Secondary: LBW, very LBW, neonatal morbidity, duration of admission to NICU or hospital, death, treatment side effects, persistent infection, recurrent infection, failure of treatment, economic analysis, false positive/negative result of screening program and women’s satisfaction | Preterm birth for LBW (RR 0.48 95% CI 0.34-0.66) and very LBW (RR 0.34 95% CI 1.5-0.75) was significantly lower in the intervention group than in the control group. |  |
O’Connor et al.[29] | 55 (1983-2006) | The use of decision making aids for people facing difficult screening decisions | Use of decision aids when providing information about screening | The use of decision aids are better than usual care in relation to knowledge (MD 15.2 out of 100 95% CI 11.7 to 18.7), decisional conflict related to feeling uninformed (MD -8.3 of 100; 95% CI -11.9 to -4.8), risk perceptions and reduced passive involvement in decisions (RR 0.6; 95% CI 0.5 to 0.8) | Yes |
Supplementation | |||||
Blencowe et al.[30] | 19 | Folic acid supplementation | Neonatal mortality from NTD | FA supplementation in women with previous pregnancy with NTD: 70% reduction (95% CI 35-86) (3xRCT) | Yes |
Lumley et al.[31] | 4 (1981-1999) | Periconceptual supplementation with folate/multivitamins | NTD incidence | ↓incidence of NTD (RR 0.28, 95% CI 0.13 to 0.58) | Yes |
Pena-Rosas & Viteri [32] | 49 (1958-2008) | Iron supplementation in pregnancy | Maternal: premature delivery, Hb at term, anaemia at term, iron deficiency at term, iron-deficiency anaemia at term, side effects Infant: LBW, birthweight | Daily iron supplementation associated with ↑ Hb at term (MD 6.00 95% CI 2.75-9.25, high quality trials only included in MA) before & after birth and ↓risk of anaemia at term (RR 0.46; 95% CI 0.29 to 0.72, MA from 4 high quality trials) | Yes |
Shah et al.[33] | 13 (1998-2007) | Prenatal micronutrient supplementation | Pregnancy outcome, low birth weight, pre term birth, SGA, birth weight & gestational age | Reduction in risk of LBW (RR 0.81 95%CI 0.73-0.91) compared with placebo or folic acid RR 0.74 95% CI 0.74-0.93). Birth weight higher (WMD 54g 95%CI 36-72g) | Yes |
Hofymeyr et al.[34] | 11 (1987-1999) | Calcium supplementation | Maternal: ↑B/P with or without proteinuria, ↑B/P with significant proteinuria, Infant: preterm delivery, birthweight, admission to NICU, stillbirth or death | Pre-eclampsia ↓(RR 0.68, 95% CI 0.57-0.81) | Yes |
 |  |  |  | Fewer babies born <2500g (RR 0.83 95% CI 0.71-0.98) |  |
Hofmeyr et al.[35] | 12 (1987-2006) | Calcium supplementation | Maternal: ↑B/P with or without proteinuria, ↑B/P with significant proteinuria, maternal death or serious morbidity | B/P ↓ with supplementation (RR 0.7, 95% CI 0.57-0.86) | Yes |
 |  |  |  | Pre-eclampsia ↓(RR 0.48, 95% CI 0.33-0.69) |  |
 |  |  |  | Maternal death/morbidity ↓(RR 0.80 95% CI 0.65-0.97) |  |
 |  |  |  | Comment from author: possible benefit in research to investigate calcium at community level |  |
Hofymeyr et al.[36] | 13 (1987-2009) | Calcium supplementation | Maternal: ↑B/P with or without proteinuria, ↑B/P with significant proteinuria, maternal death or serious morbidity, placental abruption, C/S, proteinuria, severe pre-eclampsia, eclampsia, HELLP syndrome, ICU, maternal death, mother’s hospital stay seven days or more | Risk of ↑B/P reduced (RR 0.65, 95% CI 0.53-0.81) | Yes |
 |  |  | Infant: Preterm birth, LBW, SGA, admission to NICU, neonate in NICU >7days stillbirth or death before discharge from hospital, death or severe neonatal morbidity | Risk of preeclampsia reduced (RR 0.45, 95% CI 0.31-0.65) |  |
 |  |  |  | Effect was greatest for high risk women (RR 0.22, 95% CI 0.12 to 0.42) and women with low baseline calcium (RR 0.36, 95% CI 0.20 to 0.65) |  |
 |  |  |  | Maternal death or serious morbidity reduced (RR 0.80 95% CI 0.65-0.97 |  |
Horvath et al.[37] | 4 (1995-2000) | Advice regarding polyunsaturated fatty acids supplementation to women in high-risk pregnancies | Duration of pregnancy, preterm delivery (PTD), (birth weight, occurrence of intrauterine growth retardation (IUGR) | Significantly lower rate of PTD <34 wks (RR 0.39, 95% CI 0.18-0.84). (from 2xRCT, n=291) | Yes |
Support | |||||
Hatem et al.[38] | 11 (1989-2003) | Midwifery led models of care | 1. Antenatal: mean number of antenatal visits, antenatal hospitalisation, APH, fetal loss and neonatal death <24wks, fetal loss or neonatal death ≥ 24wks, total fetal loss and neonatal death | -Women who had midwife-led models of care were less likely to experience antenatal hospitalisation, (RR 0.90 95% CI 0.81-0.99), regional analgesia (RR 0.81, 95%CI 0.73-0.91), episiotomy(RR 0.82, 95% CI 0.77-0.88), and instrumental delivery (RR 0.86, 95% CI 0.78 to 0.96) | Yes |
 |  |  | 2. Labour: amniotomy, augmentation/artificial oxytocin during labour, no intrapartum analgesia/ anaesthesia, regional analgesia, opiate analgesia, mean labour length, IOL | -Women were more likely to experience no intrapartum analgesia/anaesthesia (RR 1.16, 95% CI 1.05-1.29), SVB (RR 1.04, 95% CI 1.02-1.06), feeling in control during childbirth (RR 1.74, 95% CI 1.32-2.30), attendance at birth by a known midwife (RR 7.84, 95% CI 4.15-14.81) and initiate breastfeeding (RR 1.35, 95% CI 1.03 to 1.76) |  |
 |  |  | 3. Delivery and immediate postpartum: C/S, attendance at birth by known carer, instrumental vaginal birth, SVB, episiotomy, perineal laceration requiring suturing, intact perineum, PPH, maternal death, duration of postnatal hospital stay (days) | -No difference between groups for C/S births (RR 0.96, 95% CI 0.87-1.06). |  |
 |  |  | 4. Neonatal: LBW, preterm birth, Apgar score <7 at 5 mins, admission to SCU, NICU, mean length of neonatal hospital stay, neonatal convulsions, cord blood acidosis, maternal postpartum, postpartum depression, breastfeeding initiation, any breastfeeding at three months, prolonged perineal pain, pain during sexual intercourse, Urinary incontinence, faecal incontinence, prolonged backache, high perceptions of control during labour and childbirth | -Women who were randomised to receive midwife-led care were less likely to experience fetal loss before 24 weeks’ gestation (RR 0.79, 95% CI 0.65-0.97) |  |
 |  |  |  | -No statistically significant differences in fetal loss/neonatal death of at least 24 weeks (RR 1.01, 95% CI 0.67-1.53) or fetal/neonatal death overall (RR 0.83, 95% CI 0.70-1.00) and their babies were more likely to have a shorter length of hospital stay (mean difference -2.00, 95%CI -2.15 to -1.85) |  |
Hodnett & Fredericks [39] | 18 (1986-2001) | Additional emotional support, with information and advice, to women at risk of PTD or delivering a LBW baby | PTD, birth weight (mode of delivery, pregnancy outcome, psychosocial outcomes) | Offering additional emotional support was not associated with improved perinatal outcomes. | Yes |
 |  |  |  | Associated reduction in caesarean births (RR 0.88, 95% CI 0.79-0.98) and an increase in likelihood of elective termination of pregnancy (RR 2.96, 95% CI 1.42-6.17). |  |
Dennis & Kingston [40] | 14 (1986-2004) | Telephone support during pregnancy and early postpartum | Smoking abstinence, smoking relapse, smoking cessation, preterm birth, LBW, breastfeeding, postpartum depression | Reduction in LBW (3 trials, n=2,027; RR=0.78, 95% CI 0.63-0.97) | Yes |
 |  |  |  | Improved continuation of any breast feeding (3 trials, n=618; RR=1.18, 95% CI 1.05-1.33) and exclusive breast feeding (2 trials, n=295; RR=1.45, 95% CI 1.12-1.87) |  |
 |  |  |  | Postpartum depression: significant effect at 4 weeks (RR 0.24 95% CI 0.06-1.00) and 8 weeks (RR 0.30 95% CI 0.10-0.92) based on pilot trial data |  |
 |  |  |  | Some methodological limitations of trials included and majority of MA conducted with small number of studies |  |
Education | |||||
Lumley et al.[41] | 72 (1975-2008) | Promotion of smoking cessation in pregnancy | Smoking cessation, smoking reduction, birth weight, mode of birth, perinatal outcomes, breastfeeding, gestation, psychological measures, withdrawals | Significant reduction in smoking in late pregnancy (RR 0.94, 95% CI 0.93-0.96) | Yes |
 |  |  |  | Reduction in LBW (RR 0.83, 95% CI 0.73 -0.95) and preterm birth (RR 0.86, 95% CI 0.74-0.98) |  |
 |  |  |  | 53.91g (95% CI 10.44 g to 95.38 g) increase in mean birth weight |  |
Naughton et al.[42] | 15 (1985-2003) | Self help smoking interventions in pregnancy -written, audio, telephone or computer based | Effectiveness of self help on cessation of smoking | Self help more effective: 13.2% quit rate v 4.9% (OR 1.83 95% CI 1.23-2.73) | Yes |
Hay-Smith et al.[43] | 16 (1987-2007) | Pelvic floor muscle training | Self-reported urinary or faecal incontinence | Women without prior incontinence were less likely to report incontinence in late pregnancy (RR 0.44 95% CI 0.30-0.65) and up to 6 mths postpartum (RR 0.71 95% CI 0.52-0.97) | Yes |
 |  |  |  | Pregnant women with persistent incontinence 3mths after delivery and received PMFT less likely to report urinary incontinence at 12 mths post delivery (RR 0.79 95% CI 0.70-0.90) and less likely to report faecal incontinence at 12 mths (RR 0.52 95%CI 0.31-0.87) |  |
Lemos et al.[44] | 4 (1998-2004) | Perineal exercises during pregnancy | Prevention of urinary incontinence | Significantly reduced development of urinary incontinence from 6 weeks to 3 mths after delivery (OR 0.45 95% CI 0.3-0.66) 4x RCT, n=675 | Yes |
Mental Health | |||||
Dennis & Creedy [45] | 15 (1966-04) | Psychosocial and psychological interventions for preventing postpartum depression | Postpartum depression/ psychosis Maternal mortality | Women receiving psychosocial interventions were equally likely to develop depression as those receiving standard care (RR 0.81, CI 0.65-1.02). | Yes |
 |  |  |  | Identifying mothers at risk assisted prevention of postpartum depression (RR 0.67, CI 0.51-0.89) |  |
 |  |  |  | Interventions with only postnatal component more beneficial than those also incorporating antenatal component (RR 0.76, CI 0.58-0.98) |  |
 |  |  |  | Individually based interventions more effective than group based (RR 0.76, CI 0.59-1.00) |  |
 |  |  |  | No preventive effect of psychological debriefing (RR 0.57 CI, 0.31-1.04) |  |
Intranatal | |||||
Clinical Care | |||||
Cluett & Burns [46] | 11 (1993-2007) 11xRCT | Immersion in water for labour or birth | Maternal outcomes (mortality, morbidity & labour) | First stage of labour: significant reduction in the epidural/ | Yes |
 |  |  | Fetal outcomes (abnormal heart rate, meconium, birth weight & gestational age) | spinal/paracervical analgesia/ |  |
 |  |  | Neonatal outcomes (morbidity & mortality) | anaesthesia rate amongst women allocated to water immersion compared to controls (478/1254 versus 529/1245; (OR) 0.82, 95% CI 0.70-0.98, p 0.025) 6xRCT |  |
 |  |  | Care giver outcomes (satisfaction & injury) |  |  |
Rabe et al.[47] | 7 (1988-2000) | Early umbilical clamping in pre term infants | Requirement for resuscitation | Delayed clamping associated with fewer transfusions for anaemia (RR 2.01, 95% CI 1.24-3.27) 3x RCT, n=111 | Yes |
 |  |  | Apgar score at 5 & 10 mins | low B/P (RR 2.58, 95% CI 1.17 to 5.67) 2x RCT, n=58 |  |
 |  |  | Hypothermia during first hour of life on admission or in labour ward | less IVH (RR 1.74, 95% CI 1.08-2.81) 5xRCT, n=225 |  |
 |  |  | Death | No difference in other outcomes |  |
 |  |  | (B/P, IVH) |  |  |
Environment | |||||
Hodnett et al.[48] | 9 (1984-2009) | Alternative v conventional settings for birth | Spontaneous vaginal birth. | Alternative setting increased likelihood of no intrapartum analgesia/anaesthesia (RR 1.17, 95% CI 1.01-1.35), SVB (RR 1.04, 95% CI 1.02-1.06), positive views of care (RR 1.96, 95% CI 1.78-2.15), breastfeeding at 6-8 wks (RR 1.04, 95% CI 1.02-1.06) decreased episiotomy rate (RR 0.83, 95% CI 0.77-0.90) | Yes |
 |  |  | Maternal death or serious maternal morbidity | no effect on serious perinatal or maternal morbidity/mortality |  |
 |  |  | Use of analgesia/anaesthesia for labour or birth. |  |  |
 |  |  | Labour augmentation with artificial oxytocics. |  |  |
 |  |  | Views of intrapartum care |  |  |
 |  |  | Perinatal death or serious perinatal morbidity |  |  |
Hodnett et al.[49] | 16 (1989-2006) 16x RCT | Provision of continuous support for women during childbirth | Labour: ARM, oxytocin, EFM, epidural analgesia, any analgesia/anaesthesia, severe pain, labour length. | Women who had continuous intrapartum support were likely to have a slightly shorter labour, (WMD -0.43 hours, 95% CI -0.83 to -0.04), were more likely to have a spontaneous vaginal birth (RR 1.07, 95% CI 1.04 to 1.12) and less likely to have intrapartum analgesia ( RR 0.89, 95% CI 0.82- 0.96) or to report dissatisfaction with their childbirth experiences (RR 0.73, 95% CI 0.65- 0.83) | Yes |
 |  |  | Birth events: C/S, operative vaginal birth, SVB, episiotomy, perineal trauma |  |  |
 |  |  | Newborn events: low 5min APGAR, low cord pH, admission to SCU, prolonged newborn hospital stay |  |  |
 |  |  | Immediate maternal psychological outcomes: feeling tense, anxious during labour, negative rating of/negative feeling about the experience, perceived difficulty in coping with labour, perceived low control during labour |  |  |
 |  |  | Longer-term maternal outcomes: PND, low self-esteem in the postpartum period, anxiety in the postpartum period, difficulty mothering, less than full breastfeeding, prolonged perineal pain, pain during sexual intercourse, urinary incontinence, faecal incontinence; |  |  |
Chaillet & Dumont [50] | 10 (1992-2005) | Evidence based strategies to reduce C/S rate | Reduction in C/S rate | Significant reduction in all studies of C/S rate (RR 0.81 95% CI 0.75-0.87) | Yes |
 |  |  |  | Types of strategies effective to reduce C/S rate were audit & feedback (RR 0.87 0.81-0.93), quality improvement (RR 0.74, 95% CI 0.70-0.77) and multifaceted strategies (RR 0.73 95% CI 0.68-0.79) |  |
 |  |  |  | Studies including an identification of the barriers to change were more effective (RR 0.74 95% CI 0.71-0.78) than studies which did not (RR 0.88 95% 0.82-0.96) |  |
Postnatal | |||||
Breast Feeding | |||||
Britton et al.[51] | 34 (1979-2004) | Additional support for breastfeeding mothers | Duration of any breastfeeding (exclusive/ partial breastfeeding) | All forms of additional support resulted in longer duration of any breastfeeding (RR 0.91, 95% CI 0.86-0.96), with the largest effect on exclusive breastfeeding than any (RR 0.81, 95% CI 0.74-0.89). | Yes |
 |  |  |  | Lay and professional support together extended any breastfeeding significantly (before 4-6wks RR 0.65, 95% CI 0.51-0.82; before 2 mths RR 0.74, 95% CI 0.66-0.83) Exclusive breastfeeding significantly prolonged with WHO/UNICEF training (RR 0.69, 95% CI 0.52-0.91). |  |
 |  |  |  | Face-to-face contact with mothers more useful than telephone contact. |  |
Chung et al.[52] | 38 (2001-2007) | Promotion of breastfeeding through education, support or other component | Breastfeeding rates (initiation, duration and exclusivity) | Breastfeeding interventions increased rates of short-term (1-3mths) and long-term (6-8mths) exclusive breastfeeding (RR 1.28, 95% CI 1.11-1.48 and RR 1.44, 95% CI 1.13-1.84) although statistically significant heterogeneity was noted for short term exclusive breast feeding (I2 =55%; p= 0.006). | Yes |
 |  |  |  | Increased rate (22%) of any (RR 1.22 95%CI 1.08-1.37) and exclusive (RR 1.65 95%CI 1.03-2.63) short term breastfeeding with interventions that included a component of lay support. |  |
 |  |  |  | Pre- and postnatal breastfeeding interventions together had a larger effect than either alone. |  |
 |  |  |  | Inclusion of lay support was more effective than usual care in increasing short term rates. |  |
 |  |  |  | No evidence to support formal breastfeeding education with individual level professional support for increasing initiation rates. |  |
Sikorski et al.[53] | 20 (1979-2001) | Additional support for breastfeeding mothers vs. standard care | Breastfeeding rates: duration and exclusivity | Additional professional support was more beneficial than standard care for duration of any breastfeeding (RR 0.89, 95% CI 0.81-0.97) 10xRCT, n=19,696 6xRCT, n=18,258 | Yes |
 |  |  |  | Additional lay support was effective in reducing the cessation of exclusive breastfeeding (RR 0.66, 95% CI 0.49-0.89), 5xRCT, n=2530 |  |
 |  |  |  | Effect sizes for interventions with a postnatal element alone were (RR 0.80, 95% CI 0.80-0.96). |  |
 |  |  |  | Four trials using WHO/UNICEF training showed significant benefit in prolonging exclusive breastfeeding (RR 0.70, 95% CI 0.53-0.93) |  |
Dyson et al.[54] | 11 (1987-2004) | Interventions occurring before the first feed to promote initiation of breastfeeding | Breastfeeding initiation rates | Five studies (n=582) showed breastfeeding education had a significant effect on increasing breastfeeding initiation rates compared to standard care (RR 1.57, 95% CI 1.15-2.15, p=0.005) in low income groups. Substantial statistical heterogeneity noted (I2=53.4%) | Yes |
 |  |  |  | One-to-one, needs-based, informal repeat education sessions and formal antenatal education sessions were effective (2 studies, n=162, RR 2.40, 95% CI 1.57-3.66, Z = 4.05; p= 0.000051) in increasing breastfeeding rates among low income mothers regardless of ethnicity & feeding intention. Statistical heterogeneity small (I2=7.0%) |  |
 |  |  |  | One study (n=165) showed needs-based, informal peer support in antenatal and postnatal periods was effective (RR 4.02, 95% CI 2.63-6.14, p<0.00001) in increasing initiation but not seen at 1 or 3 months post partum. |  |
Moore et al[55] | 35 (1976-2005) | Early skin to skin contact | Breastfeeding status (exclusivity) and duration | Statistically significant and positive effects of early skin to skin on breastfeeding at one to four months post birth (10 trials; 552 participants (OR 1.82, 95% CI 1.08-3.07) and breastfeeding duration (seven trials; 324 participants WMD 42.55, 95% CI -1.69 -86.79) | Yes |
 |  |  | Success of the first breastfeeding |  |  |
 |  |  | Breastfeeding problems such as breast engorgement, infant latch-on difficulties, sore nipples; |  |  |
 |  |  | Breast milk maturation; Changes in infant physiological parameters during and after skin-to-skin contact (Additional outcomes considered-see reference) |  |  |
Ahmed & Sands [56] | 8 (1999-2008) | Breast feeding interventions inc kangaroo care, peer counselling, in home breast milk measurement, post discharge lactation support | Duration | Kangaroo care, peer counselling, in home breast milk measurement, and post discharge lactation support improved breast feeding outcomes | No |
 |  |  | Exclusivity | Maternal satisfaction improved with post discharge support |  |
 |  |  | Maternal satisfaction | No impact on weight gain |  |
 |  |  | Weight gain |  |  |
Mental Health | |||||
Dennis & Hodnett [57] | 9 (1966-2006) | Postnatal psychosocial and psychological interventions | Postpartum depression | Psychological and psychosocial interventions were effective in decreasing depressive symptomatology within the first year postpartum (RR 0.70, CI 0.6 to 0.81). | Yes |
 |  |  | Maternal mortality |  |  |
Education & Support | |||||
Amorim Adegboye et al.[58] | 6 (1994-2003) | Diet, exercise or both for weight reduction postpartum | Change in body weight (kg), % of women who returned to pre pregnancy weight or lost weight retained after childbirth, % of women who achieved healthy weight, | Both women who took part in a diet (1 trial, n=45, WMD -1.70 kg; 95% CI -2.08 to -1.32, z=8.73; p<0.00001), and women on a diet plus exercise programme (4 trials, n=169, WMD -2.89 kg; 95% CI -4.83 to -0.95; z=2.92; p<=0.00049), lost significantly more weight than women in the usual care | Yes |
Corcoran & Pillai [59] | 16 (1970-2004) | Repeat pregnancy prevention programmes, including education and counselling (majority hospital-based interventions) for teenagers | Rates of repeat pregnancy | The prevention programme saw a 50% reduction in the odds of repeat pregnancy when compared to comparison-control conditions at mean 19.13 mths (OR 0.474, 95% CI 0.322-0.695), but the effect dissipated by mean 31 mths. | Yes |
Pinquart & Teubert [60] | 142 (not given) | Parenting education with new parents | Parenting stress | Small effects on parenting, parental stress, child abuse, health promoting behaviour, cognitive, Social development, motor development, child mental health, parental mental health & couple adjustment | Yes |
 |  |  | Parenting quality |  |  |
 |  |  | Health promoting behavior |  |  |
 |  |  | Child abuse and neglect |  |  |
 |  |  | Child development |  |  |
 |  |  | Mental health of parents |  |  |
 |  |  | Couple adjustment |  |  |
Vanderveen et al.[61] | 25 (1980-2006) | Early parental intervention for premature infants-varied but all involved teaching/enhancing parents skills or involving parents in aspects of care | Primary outcome: neurodevelopment other outcomes discussed in subsequent paper(not specified in paper, available from authors) | 12 studies: Higher mental performance scores at 12 months (WMD 5.57 95% CI 2.29-8.86 p=0.0009) and at 24 months (7 studies, WMD 7.59 95% CI 5.01-14.31 p=0.0003) and at 36 months (2 studies, WMD 9.66 95% CI 5.01-14.31 p=0.0001) but not at 5 yrs (3 studies p=0.24) | Yes |