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Abstract
Objectives This study aimed to assess the spatial distribution, wealth-related inequality and determinants for delayed initiation of antenatal care (ANC) visits among reproductive-age women in Ethiopia.
Design Cross-sectional study design.
Setting Ethiopia.
Participants A total of 2924 reproductive-age women who had given birth in the 5 years preceding the survey.
Outcome measure Delayed initiation of ANC visits.
Results The magnitude of delayed initiation of ANC visits among reproductive-age women in Ethiopia was 62.63% (95% CI 60.86%, 64.37%). Women aged 35–49 (AOR=1.42; 95% CI 1.04, 1.94), being protestant religion followers (AOR=1.43; 95% CI 1.06, 1.94), being in higher wealth index (AOR=0.53; 95% CI 0.41, 0.69), living in rural residence (AOR=1.50; 95% CI 1.02, 2.19) and living in the metropolitan region (AOR=0.45; 95% CI 0.26, 0.77) were significantly associated with delayed initiation of ANC visit. Southern Nations Nationalities and Peoples Region (SNNPR), Somalia, Benishangul Gumuz, Southern Addis Ababa and Gambella regions were hot spot regions for delayed initiation of ANC visits. The SaTScan analysis result identified 107 primary clusters of delayed initiation of ANC visits located in regions of SNNPR, Gambella, Southern Addis Ababa, Eastern Oromia and Benishangul Gumuz.
Conclusions Significant spatial clustering of delayed initiation of ANC visits was observed in Ethiopia. More than half of women had delayed initiation of ANC visits in Ethiopia. Women’s age, religion, wealth index, residence and region were significant predictors of delayed initiation of ANC visits. There is a disproportional pro-poor distribution of delayed initiation of ANC visits in Ethiopia. Therefore, interventions should be designed in the hot spot areas where delayed initiation of ANC visits was high to enhance the timely initiation of ANC visits.
- public health
- preventive medicine
- international health services
Data availability statement
Data are available upon reasonable request. The datasets used and/or analysed during the current study are available from the corresponding author upon reasonable request.
This is an open access article distributed in accordance with the Creative Commons Attribution Non Commercial (CC BY-NC 4.0) license, which permits others to distribute, remix, adapt, build upon this work non-commercially, and license their derivative works on different terms, provided the original work is properly cited, appropriate credit is given, any changes made indicated, and the use is non-commercial. See: http://creativecommons.org/licenses/by-nc/4.0/.
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STRENGTHS AND LIMITATIONS OF THIS STUDY
The use of nationally representative data sets tends to increase the generalisability of the results.
Given the cross-sectional nature of the data, it is unable to establish any causal links between outcome and independent variables.
Since this survey relies on respondents’ self-report, there may be the possibility of recall bias.
Introduction
Maternal mortality, or the death of a woman during pregnancy, childbirth or in the 42 days following delivery, continues to be a significant challenge for global health systems.1 Antenatal care (ANC) is one of the most crucial strategies for reducing maternal and neonatal morbidity and mortality by diagnosing and treating pregnancy-related illnesses.2 ANC benefits include the treatment and prevention of complications, emergency preparedness, birth planning, patient education, successful newborn care and nutrition, and encouragement of male partner involvement in ANC.3
ANC is an important point of entry for pregnant women to start receiving health promotion and preventive information and services, such as iron supplements, deworming tablets, tetanus injections and malaria prophylaxis.4 5 It also includes the identification of risk groups, disease prevention and treatment during pregnancy, and health education services.6 ANC aims at promoting pregnant women’s health and has been found to lower the chance of unfavourable pregnancy outcomes.7 8
The development of the fetus during the first trimester is critical.9 The first trimester of pregnancy is the most rapid developmental phase for the fetus, during which all of the organ systems are fully developed.10 Early first ANC visit is an essential healthcare service for women and newborn babies.11 WHO recommended initiation of ANC attendance not later than the first trimester (before the gestational age of 12 weeks) of pregnancy.12 13
Early ANC visits have been shown to predict the provision of WHO-recommended interventions.14–16 The early start of ANC ensures that women receive an adequate number of visits and services.17 According to studies, women who began ANC early and attended the recommended number of visits were more likely to be assisted during delivery by a skilled attendant compared with those who started ANC late and attended just a few visits.18–20
Even though ANC services are provided without fee and are readily available, low ANC usage and late initiation of the first ANC visit remain major issues.21 22 Late initiation of ANC may lead to adverse outcomes, such as low birth weight and premature birth.23 The delayed initiation of the first ANC visit may result in a missed opportunity for the reduction of complications, and the development of an interventional plan for possible adverse pregnancy consequences.24 Despite this, many women attend their first antenatal visit with a pregnancy that has already been compromised due to fetomaternal complications.25 26
Evidence also indicated that wealth and education are the most significant contributors to socioeconomic inequalities in ANC usage.27 The use of ANC services by socioeconomic status reveals significant disparities between the rich and the poor.28–30 Socioeconomic inequality in skilled ANC service usage continues to be the major difficulty in Ethiopia.28 Previous studies about the impact of socioeconomic inequality on ANC usage overlooked its effect on the timing of ANC visits.31–34 We have assessed the level of socioeconomic inequalities of delayed initiation of ANC visits in Ethiopia using Wagstaff’s normalised concentration index.
Evidence suggests that there is regional variation in the delayed initiation of ANC visits across Ethiopia.35–37 As, geographic disparities in healthcare services pose policymakers and practitioners with a challenge,38 assessing the geographical pattern of delayed initiation of ANC visit using the most recent 2019 Ethiopian Demographic and Health Survey (EDHS) data is critical for planning and implementing geographically focused interventions that will enhance the timely initiation of ANC visits in Ethiopia.
Previous research on the timing of ANC visits in Ethiopia was conducted in specific areas with small sample sizes and mainly focused on individual-level factors.10 39–43 Hence, this study aimed to assess the individual and community level determinants, socioeconomic inequities, and regional disparities for delayed initiation of ANC visits among reproductive-age women in Ethiopia using the most recent nationally representative data.
Methods
Study design and setting
A cross-sectional study design was conducted in Ethiopia using the intermediate EDHS 2019 which was conducted by the Central Statistical Agency in partnership with the Federal Ministry of Health and the Ethiopian Public Health Institute. Ethiopia is an East African country with nine regional states and two city administrations (Addis Ababa and Dire Dawa), administratively, regions are divided into zones, zones into woredas and woredas into the lowest administrative unit known as kebeles.
Data source
The 2019 Ethiopian mini Demographic and Health Survey (EMDHS) dataset was used for this study, which was the second EMDHS and the fifth DHS implemented in Ethiopia conducted from 21 March 2019 to 28 June 2019. Data were obtained from the DHS website: www.dhsprogram.com by justifying the reason for requesting the data and after obtaining an approval letter from the DHS. The individual record data set was used.
Sampling procedures and populations
A two-stage stratified cluster sampling was used. Each region was divided into urban and rural areas, resulting in 21 different sampling strata. First, a total of 305 enumeration areas (EAs) (93 in urban, 212 in rural) were chosen independently with a probability proportional to each EAs. Second, from the newly formed household listing, a fixed number of 30 households/clusters were selected with an equal probability of systematic selection. The detailed sampling procedures are available on the measure DHS website in the 2019 EMDHS report (https://www.dhsprogram.com). We used the individual record data set for this study, and the study population consisted of reproductive-age women (aged 15–49 years) who had given birth in the 5 years preceding the survey. Finally, a total weighted sample of 2924 participants was included in this study.
Study variables
The outcome variable for this study was delayed initiation of ANC visit which is defined as booking the first ANC after 12 weeks of gestation.44 Individual and community-level independent variables were considered in this research. Maternal age, marital status, maternal educational level, religion, household head, household wealth and parity were some of the individual-level factors included in this study. As community-level factors, residence and region were considered. In this study region was categorised into three categories; larger central (Tigray, Amhara, Oromia and Southern Nations Nationalities and Peoples Region (SNNPR)), small peripherals (Afar, Somali, Benishangul and Gambela) and metropolis (Harari, Dire Dawa and Addis Ababa) based on their geopolitical features, which is consistent with a prior Ethiopian study.37 45 46
Data processing and analysis
The data was cleaned to ensure consistency with the EMDHS 2019 report. STATA V.16.0 was used for recoding, variable generation, labelling and analysis based on the Guide to DHS Statistics. To restore the survey’s representativeness and obtain valid statistical estimates, we weighted for sample probabilities and non-response using the weighting factor provided in the EDHS data. Due to the clustered nature of the EDHS data women were nested in a cluster and women in the same cluster may have characteristics in common with women in another cluster, which violates the classic logistic regression model assumption of independent observations and equal variance between clusters. Therefore, we performed a multilevel logistic regression which takes into account the heterogeneity between clusters with a random effect applied at the cluster level and assumes that each community has a different intercept (β0) and fixed coefficient (β). As candidates for the adjusted model, factors with a p value of 0.2 in crude OR were selected. Therefore, to assess the strength of the relationship between the independent variable and the dependent variables, the OR was estimated with 95% CI using a p value <0.05 and was considered to declare a statistically significant association. The spatial analysis was done using ArcGIS V.10.7 and SaTScan V.9.6 software.
Model building
Four models have fitted: the null model (models without independent variables), model I (models with individual-level variables), model II (models with community-level variables) and model III (models with both individual and community-level variables). The model’s fitness was evaluated using deviance information criteria. The variance inflation factor (VIF) was used to detect multicollinearity.
Parameter estimation method
The random effects, which are measures of variation in delayed initiation of ANC visits across communities or clusters, were expressed in terms of the intraclass correlation (ICC), the median OR (MOR) and the proportional change in variance (PCV).47–49 MOR is defined as the central value of the OR between the greatest and lowest risk regions when two clusters are selected at random. The PCV explains the variability in delayed initiation of ANC visits among reproductive-aged women. The ICC shows the differences between clusters in the delayed initiation of ANC visits among reproductive-aged women.50 51 The fixed effect result is reported as an adjusted OR with a 95% CI and variables with p values ≤0.05 were declared statistically significant.
Concentration index and curve
This study used a concentration index to quantify the degree of socioeconomic inequality in delayed initiation of ANC visits, which is the most appropriate measure of health inequality.52 53 A negative sign indicates a higher concentration of delayed initiation of ANC visits among the poor, whereas a positive sign indicates a higher concentration among the wealthy. The socioeconomic-related inequality in delayed initiation of ANC visits was depicted graphically using concentration curves. The concentration curve represents the cumulative proportion of delayed initiation of ANC visits (on the ordinate) compared with the cumulative proportion of the population categorised by socioeconomic status (on the abscissa).54
Spatial analysis
Spatial distribution and autocorrelation
Spatial autocorrelation (Global Moran’s I) statistic measure was used to assess whether delayed initiation of ANC visits was dispersed, clustered or randomly distributed in Ethiopia. Moran’s I value close to −1 indicates dispersed delayed initiation of ANC visit, close to +1 indicates clustered delayed initiation of ANC visit and Moran’s I value of zero indicates randomly distributed.55
Hot spot analysis
Hot Spot Analysis (Getis-Ord Gi* statistic) of the z-scores and significant p values tells areas with hot or cold spot values clustered in space. The hot spot areas indicated areas with a high proportion of delayed initiation of ANC visits and the cold spot ones indicated that there was a low proportion.
Spatial interpolation
The spatial interpolation technique is used to predict the delayed initiation of ANC visits for unsampled areas based on sampled clusters. We used a geostatistical ordinary Kriging spatial interpolation technique using ArcGIS V.10.7 software for unsampled cluster prediction.
Spatial scan statistics
The spatial scanning statistics in the Bernoulli model are used to determine the geographic location of statistically significant clusters for delayed initiation of ANC visits using Kuldorff’s SaTScan V.9.6 software.56 The scanning window that moves across the study area in which women had delayed initiation of ANC visits were taken as cases and those women who had early first ANC visits were taken as controls to fit the Bernoulli model. The default upper limit of 50% of the population was used to detect both tiny and large clusters. Using likelihood ratio and p value tests the most probable cluster was determined based on 999 Monte Carlo replicates.
Patient and public involvement
Patients and/or the public were not involved in the design, or conduct, or reporting, or dissemination plans of this research.
Results
This study included a weighted sample of 2924 women. The delayed initiation of ANC visits among women was 62.63% (95% CI 60.86%, 64.37%) in Ethiopia. Among these women, around half, 1550 (53.03%) were between the ages of 25 and 34 years. The majority of participants, 2051 (70.19%) lived in rural areas. About two-thirds, 1282 (43.87%) of the women had no formal education. Women who had no education were more likely to have delayed initiation of ANC visit 878 (68.49%) than those who had secondary and higher education 252 (51.68%). Likewise, women who live in rural areas were more likely to have delayed initiation of ANC visit 1404 (68.45%) than those who live in urban areas 426 (48.93%) (table 1).
Characteristics of the study population with delayed initiation of antenatal care (ANC) visit among reproductive-age women, 2019 mini Ethiopian Demographic and Health Survey
Random effect and model comparison
The ICC in the null model was 18%, indicating that variations in delayed initiation of ANC visits among study participants were attributed to cluster differences. The MOR value (2.25) in the null model also revealed that the odds of having delayed initiation of ANC visits among study subjects were different between clusters by this average median value. Furthermore, the PCV value in the final model revealed that both individual and community-level factors explained approximately 46% of the variability in delayed initiation of ANC visits among study subjects. Deviance was used for model comparison and fit. Model III, which had the lowest deviance, was the best-fitted model (3519). All variables had VIF values of less than 10, and the final model’s mean VIF value was 1.57 indicating the absence of multicollinearity (online supplemental table S1).
Supplemental material
Wealth-related inequality of delayed initiation of ANC visit among reproductive-age women in Ethiopia
The Wag staff normalised concentration index (C) and curve were calculated for the most recent EDHS (mini EDHS 2019) to assess the wealth-related inequality of delayed initiation of ANC visits among reproductive-aged women in Ethiopia. Delayed initiation of ANC visits was found to be significantly and disproportionately concentrated in poor households (pro-poor distribution) with (C=−0.26; 95% CI −0.29, –0.23). The concentration curve also indicated that the distribution line of delayed initiation of ANC visits was above the line of equality. This showed that delayed initiation of ANC visits among reproductive-aged women in Ethiopia was disproportionately concentrated in the poor household (pro-poor distribution) (online supplemental figure S2).
Supplemental material
Supplemental material
Spatial and incremental autocorrelation analysis of delayed ANC visit among reproductive age women in Ethiopia: based on 2019 mini EDHS
Spatial distribution of delayed initiation of ANC visit in Ethiopia based on 2019 mini EDHS showed a significant spatial variation across the country over regions, which was found to be non-random with Global Moran’s I value of 0.872 with (p<0.0001). The incremental autocorrelation result revealed statistically significant z-scores at a peak distance of 179.126 km; 12.38 (distances; z-score) for delayed initiation of ANC visit (figure 1).
Spatial autocorrelation analysis of delayed initiation of antenatal care visit among reproductive-age women in Ethiopia, 2019 mini Ethiopian Demographic and Health Survey.
Spatial distribution of delayed initiation of ANC visit among reproductive-age women in Ethiopia
A total of 305 clusters were considered for the spatial analysis of delayed initiation of ANC visits. Each point on the map represents an EA, with a proportion of delayed initiation of ANC visits in each cluster. The red dots indicated the more intense clustering of the proportion of delayed initiation of ANC visits among reproductive-age women in Ethiopia, as shown in the figures, whereas the green dots showed a lower proportion of the problem (online supplemental figure S3).
Supplemental material
Hot spot analysis of delayed initiation of ANC visit among reproductive-age women in Ethiopia
The hot spot analysis of delayed initiation of ANC visits among reproductive-age women in Ethiopia showed that SNNPR, Somalia, Benishangul Gumuz, Southern Addis Ababa and Gambella regions were hot spot areas of delayed initiation of ANC visits in Ethiopia (figure 2).
Hot spot analysis of delayed initiation of ANC visit among reproductive-age women in Ethiopia, 2019 mini EDHS. ANC, antenatal care; EDHS, Ethiopian Demographic and Health Survey.
Spatial interpolation of delayed initiation of ANC visit among reproductive-age women in Ethiopia
Kriging interpolation of delayed initiation of ANC visits among reproductive-age women in Ethiopia over the area was increased from blue which indicates low-risk to red-coloured which indicates high-risk areas. The prevalence of high-risk areas predicted for delayed initiation of ANC visits was extremely high (ranging from 76% to 90%) in Somalia, Eastern Oromia, SNNPR and Southern Addis Ababa regions. The lower predicted delayed initiation of ANC visits was seen in Addis Ababa, Dire Dawa and Harari regions (online supplemental figure S4).
Supplemental material
SaTScan analysis of delayed initiation of ANC visit among reproductive-age women in Ethiopia
In SaTScan analysis, most likely primary and secondary clusters of delayed initiation of ANC visits among women of reproductive age were identified. The primary SaTScan contains 107 primary cluster windows was detected in SNNPR, Gambella, Southern Addis Ababa, Eastern Oromia and Benishangul Gumuz regions at 7.337838 North, 35.227543 East, a radius of 423.62 km, a total population of 1133 and 791 cases of delayed initiation of ANC visit, with a relative risk (RR) of 1.42 and log-likelihood ratio (LLR) 60.74 (p value =0.001). This indicates that women in this SaTScan window were 1.42 times at experience high risk to have delayed initiation of ANC visits as compared with children out of the windows. The secondary SaTScan window with 36 clusters was detected in Somalia, Tigray, Northern Amhara, Southern Afar and Oromia regions located at 13.427229 North, 39.827618 East, RR of 1.75 and LLR of 8.95 (p value =0.039) (figure 3).
Spatial scan statistics analysis of delayed initiation of ANC visit among reproductive age women in Ethiopia, 2019 mini EDHS. ANC, antenatal care; EDHS, Ethiopian Demographic and Health Survey; LLR, log-likelihood ratio.
Mixed effect analysis of factors associated with delayed initiation of ANC visit
Based on the final model result, maternal age, religion, wealth index, residence and region were found to be significantly associated with delayed initiation of ANC visits. The odds of having delayed initiation of ANC visits among women who were aged 35–49 were increased by 42% (AOR=1.42; 95% CI 1.04, 1.94) as compared with women who were aged 15–24. The odds of having delayed initiation of ANC visits among women who were protestant religion followers were increased by 43% (AOR=1.43; 95% CI 1.06, 1.94) than women who were Orthodox religion followers.
The odds of having a delayed initiation of an ANC visit were reduced by 47% (AOR=0.53; 95% CI 0.41, 0.69) in women with a rich wealth index compared with women with a poor wealth index. Women who live in rural residences are 50% (AOR=1.50; 95% CI 1.02, 2.19) more likely to have delayed initiation of ANC visits than those women who live in urban areas. Women who live in the metropolis region are 0.55 times less likely to have delayed initiation of ANC visits than those women who live in large central regions (AOR=0.45; 95% CI 0.26, 0.77) (table 2).
Multilevel multivariable analysis of factors associated with delayed initiation of antenatal care visits among reproductive-age women in Ethiopia, 2019 mini Ethiopian Demographic and Health Survey
Discussion
Our study examined the spatial distribution and predictors of delayed initiation of ANC visits among reproductive-age women in Ethiopia. The magnitude of delayed initiation of ANC visits among reproductive-age women was 62.63% (95% CI 60.86%, 64.37%) in Ethiopia, which is consistent with a study conducted in Ethiopia.57 58 The proportion of delayed initiation of ANC visits was lower than in previous studies in, the Hadiya zone, Ethiopia,22 59 60 Tanzania,61 Zambia62 and Nigeria.63 64 One reason for the discrepancy may be that studies defined late ANC visit initiation as beginning their first ANC visits after 16 weeks of gestation, while we defined delayed initiation of ANC visits as starting their first ANC visits after 12 weeks of gestation. The other possible explanation for the difference could be due to varying levels of awareness among mothers and the community about the importance of early initiation of ANC visits, variations in participants’ sociodemographic characteristics, as well as differences in study periods, which may be another explanation.39
Based on the final model result, maternal age, religion, wealth index, residence and region were found to be significantly associated with delayed initiation of ANC visits. In this study, women in the old age group have a substantial association with the late initiation of the first ANC visit as compared with women in the young age group. This finding is similar to a study done in Ethiopia.65 The possible justification might be, older women are less likely to have more information about the significance of early ANC booking, to be fearful about their pregnancy and to be more educated than younger women.65
Women with a rich wealth index were less likely to have delayed initiation of ANC visits than women with a poor wealth index. This finding is similar to a study done in Ethiopia66 and Cameron.67 This could be because women with a high wealth index may be able to easily attend any health services due to their increased ability to pay for healthcare and transportation.66
Women who were protestant religious followers were more likely to have delayed their first ANC visit than women who were Orthodox Christian followers. The finding is similar to a study done in Ethiopia.68 Moreover, previous studies also reported that being a protestant religion follower contributes to dropping out of the maternal continuum of care.69 Religious differences have been reported to affect both the timing and frequency of ANC visits due to differences in traditions and beliefs within each religion.70 The other possible explanation could be due to the highly organised structure of the Orthodox Church, as well as the Orthodox Church and Muslim mosque’s close relationship with the government aimed at improving positive healthy practices through the health development army.71 The concerned body should pay special attention to protestant religious followers in raising awareness about the importance of early ANC initiation.
In terms of residence, women living in rural areas had a greater effect on delayed ANC visits. This finding is in line with previous studies.36 37 57 60 66 72–74 The possible reason for this urban-rural disparity in delayed initiation of ANC visits might be the exposure to health information and awareness of the potential benefits of early ANC initiation in urban women.75 Also, women living in metropolitan areas were less likely to delay their first ANC visit than women living in large central areas. This finding is in line with other studies.37 76–78 Studies also reported that living in more developed regions appears to increase early ANC attendance.78
According to the spatial distribution and spatial clustering windows, significant clustering was also detected in the SNNPR, Gambella, Southern Addis Ababa, Eastern Oromia and Benishangul Gumuz regions. The cold spot regions were observed in Addis Ababa, Diredawa and Harari regions. Previous studies also reported that those women living in large central and small peripheral regions were more likely to have delayed initiation of ANC visits than women in metropolis regions.37 This spatial variation could be attributed to an unequal distribution of maternal health services, with the majority of maternal health services concentrated in urban areas such as metropolitan areas or city administrations. Furthermore, in city administrations, access to media and education are not issues that have a direct impact on the early start of ANC visits.68 These variations emphasise the significance of increasing geographically targeted interventions by the concerned bodies to improve maternal and child health.
The study’s main strength was that it used nationally representative data with a large sample size and used an appropriate statistical approach to accommodate the data’s hierarchical nature. However, this study had limitations in that the cross-sectional nature of the data makes it impossible to infer causality between the independent and dependent variables. Since this survey relies on respondents’ self-report, there may be the possibility of recall bias because respondents were questioned to remember events from the past. Furthermore, because it was a mini report, the EMDHS data did not include information about some predictor variables of delayed initiation of ANC visits.
Conclusion
Significant spatial clustering of delayed initiation of ANC visits was observed in Ethiopia. Even though the WHO recommends that all women begin ANC within the first 12 weeks of pregnancy, more than half of women had delayed initiation of ANC visits in Ethiopia. Women’s age, religion, wealth index, residence and region were significant predictors of delayed initiation of ANC visits. There is a disproportional pro-poor distribution of delayed initiation of ANC visits in Ethiopia implying that its distribution is more common in poor households. Therefore, public health interventions should be designed in the hot spot areas where delayed initiation of ANC visits was high to enhance the timely initiation of ANC visits.
Data availability statement
Data are available upon reasonable request. The datasets used and/or analysed during the current study are available from the corresponding author upon reasonable request.
Ethics statements
Patient consent for publication
Ethics approval
Not applicable/consent to participants is not applicable since publicly available dataset was used and no identifying participant information was obtained. The authorisation for using the data was granted from the DHS programme after explaining the purpose of the study. All methods were performed in accordance with the relevant guidelines and regulations.
Acknowledgments
We would like to acknowledge the MEASURE DHS programme for providing us data set.
References
Supplementary materials
Supplementary Data
This web only file has been produced by the BMJ Publishing Group from an electronic file supplied by the author(s) and has not been edited for content.
Footnotes
Contributors The conception of the work, design of the work, acquisition of data, analysis, and interpretation of data were done by FMA. Data curation, drafting of the article, revising it critically for intellectual content, validation, and final approval of the version to be published were done by AZA, MHA, DC, and DGB.
Funding The authors have not declared a specific grant for this research from any funding agency in the public, commercial or not-for-profit sectors.
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Competing interests None declared.
Patient and public involvement Patients and/or the public were not involved in the design, or conduct, or reporting, or dissemination plans of this research.
Provenance and peer review Not commissioned; externally peer reviewed.
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