Adolescent girls perceptions of the COVID-19 infodemic in Sierra Leone: a qualitative study in urban, peri-urban and rural Sierra Leone

Introduction

During the COVID-19 pandemic, the proliferation of misinformation (factually wrong) and disinformation (intentionally spread to promote a specific and usually biased viewpoint) significantly complicated public efforts to discern reliable, accurate health information.1 The WHO described this as an infodemic.2 The rise of digitisation and the ubiquitous use of social media and the internet have rapidly spread information. While this acceleration can help bridge information gaps quickly, it also has the potential to amplify the reach of misinformation and disinformation.

As of January 2022, Sierra Leone had a population of approximately 8 million, with mobile connections surpassing 9 million,3 suggesting a highly connected and youthful demographic. The median age was 19.3 years in 2023.4 WhatsApp usage was nearly universal,3 reflecting the country’s digital engagement. Despite only 32% having internet access and 11% being active on social media, the preference for platforms such as Facebook (16%), Messenger (4%) and Instagram (4%) was notable.3 This context underscores the challenges and opportunities in addressing the spread of rumours, which a 2021 study indicates are three times as likely to be found on social media than fact-based information.5 The youth (aged 15–35 years) form 66% of the population and have a 56% labour force participation rate, predominantly in the informal sector, with 27% not engaged in education, employment or training.6

Sierra Leone was affected by the Ebola outbreak from 2014 to 2016, with over 11 000 deaths. The country’s health system is structured to provide care through a network of hospitals, peripheral health centres and community health workers, emphasising accessibility. However, despite widespread concerns that COVID-19 would severely impact low-income countries, Sierra Leone experienced relatively low levels of both incidence and case fatality. According to reports submitted to the WHO, the country only recorded 7760 confirmed cases and 125 deaths. By mid-December 2022, 6158 679 vaccine doses had been administered.7

Misinformation and disinformation pose a significant risk to public health, particularly during infectious disease outbreaks. Research has shown that such misinformation can erode public trust in official institutions, which becomes even more problematic in low-resource settings.8 Lower levels of trust are associated with a decreased likelihood of individuals adopting recommended preventive measures against disease transmission.9 A systematic review of the H1N1 pandemic corroborates this relationship between trust and preventive action. It found that people were likelier to take precautionary measures if they trusted the information source and official health advisories. An excess of conflicting or confusing information can further erode trust in healthcare systems, complicating public understanding of the necessary steps for prevention and thus impeding efforts to break chains of transmission during epidemics.10

A study in Liberia (a country that shares borders with Sierra Leone, which was also affected by the Ebola outbreak) showed that trust becomes an issue during a health crisis when an infodemic occurs coupled with the high levels of risk and uncertainty that characterise such periods.11 For public health agencies to implement programmes and provide services during times of uncertainty, such as the COVID-19 pandemic, authorities must understand where citizens get their information and how they make sense of it. This is critical as disease outbreaks can have unintended consequences, with vulnerable groups often disproportionately affected.

In Sierra Leone, where child marriage and teenage pregnancy rates are high, it is crucial to understand the sources of information adolescent girls rely on and their perceptions of these sources. This knowledge is vital during epidemics and broader health topics, including sexual and reproductive health. Adolescent girls lost trust in the health system during the Ebola outbreak, and 82% of those who became pregnant stated that they did not feel comfortable using services provided by their local health facility.12 This loss of trust was fuelled by fear of infection and uncertainty about whether health workers could provide services, as some had abandoned their posts or turned clients away.13 The decreased use of sexual reproductive health services by adolescent girls was associated with a 42% increase in adolescent pregnancy in Kenema and 172% in Kailahun district.14 Such health outcomes are undesirable because teenage pregnancies result in more girls dropping out of education and increased risks of obstetric complications and deaths.

During the COVID-19 pandemic, misinformation about home remedies for the virus was shared on social media platforms such as WhatsApp, Twitter and YouTube. Some claimed that heat could kill the virus by exposure to the sun or hot baths.15 Other rumours claimed that health workers were being paid to infect their patients. These rumours can affect the decision to access essential healthcare services such as contraception or malaria treatment. A Sierra Leone study has shown a strong association between knowledge, trusted sources of information and crucial preventive practices for COVID-19, such as social distancing and wearing a face mask or hand washing.16 However, to our knowledge, there have been no studies that specifically investigate the information sources that vulnerable groups such as adolescent girls in urban, peri-urban and rural Sierra Leone relied on during the COVID-19 pandemic, their trust in these sources and their methods for navigating the influx of information.

This study aimed to ascertain the primary sources of COVID-19 health information for adolescent girls, evaluating which were deemed trustworthy or otherwise, and assessing their subsequent influence on the girls’ behaviour. Our objective was to gain insights into the cognitive processes that underpin adolescent girls’ decisions and actions during health crises and to explore their broader information-processing strategies regarding critical health matters, such as reproductive and sexual health. This knowledge is invaluable for policymakers and practitioners formulating strategies and interventions to shape the decisions and behaviours of adolescent girls.

Methods

Theoretical framework

This study is grounded in the social cognitive theory (SCT), which underscores the importance of observational learning, social experience and the influence of trusted sources on behaviour.17 The SCT emphasises the role of external and internal social reinforcement. It provides a robust lens to understand how adolescent girls interpret and act on the health information they receive, especially during a health crisis.

Study design

This qualitative research used focus group discussions (FGDs) in July 2020 to examine the sources of COVID-19 health information that adolescent girls considered trustworthy or otherwise. It also aimed to understand the influence of misinformation on their adherence to recommended behaviours viewed through the lens of SCT, considering the dynamics of observational learning and response to trusted sources. The selection of girls aged 15–19 years was guided only by the interests of the study’s sponsor. They also influenced the FGD interview guide’s development based on the terms of references they provided. They prioritised this age group to enhance access to adolescent sexual and reproductive health services during the pandemic.

Sampling strategy

Convenience sampling was a practical choice given the recruitment challenges presented by the COVID-19 pandemic. Recruitment was community-based as we aimed to reach girls in and out of school. In any event, schools were closed during the pandemic. The process commenced with seeking formal permission from traditional community leaders, a practice reflective of Sierra Leone’s societal structure. Headmen often fill this role in urban and peri-urban areas, while chiefs hold this responsibility in rural settings. With schools closed, researchers from the Institute for Development leveraged their networks within NGOs, previously established through earlier studies, as a vital means to engage with potential participants directly in their communities. This recruitment strategy was also instrumental in overcoming the logistical and access challenges of the pandemic’s restrictions. Following initial contacts, the confirmed participants were encouraged to recommend other girls within the target age range, thus extending the recruitment process through community-based networks. Sixteen FGDs were conducted among 86 adolescents aged 15–19 years in Sierra Leone. The FGDs involved eight participants in six groups, six in four groups and seven in two other groups. We conducted 16 FGDs because we gathered enough data to capture the full range of experiences and perspectives without needing additional groups. There were no exclusion criteria, as the study aimed to capture a broad spectrum of experiences.

Safety precautions during COVID-19

All FGDs observed strict safety protocols, encompassing social distancing, mandatory mask-wearing for participants and researchers alike, and frequent hand sanitisation. Interview locations were selected to ensure adequate spacing between the attendees. The research team underwent COVID-19 testing before their community visits, and local health guidelines were adhered to during the research.

Training and pretesting

The interview guide for FGDs was developed by the principal investigator in English, drawing from the terms of reference provided by the client and a comprehensive review of relevant literature. This included the incorporation of questions about agreement or disagreement with specific statements, which were informed by the work of Enria and Tengbeh on tracking and addressing rumours during COVID-19 in 2020 (Enria and Tengbeh, unpublished, 2020). Their research played a crucial role in shaping the content and focus of the interview guide, ensuring that the discussions were grounded in scientifically informed statements and current understandings of pandemic-related misinformation. This process ensured that the guide was aligned with the specific objectives of the study and grounded in the current academic discourse on the impact of the COVID-19 pandemic on adolescent girls’ health behaviours and perceptions. The guide was reviewed with the client and colleagues to ensure its applicability and effectiveness in eliciting deep, insightful discussions among participants. Researchers then pretested the interview guide in Krio, the local language, with five adolescent girls chosen from family members and acquaintances. No significant modifications were made to the guide after the pretesting. Field researchers from the Institute for Development (a mixed-methods research institute in Sierra Leone) were then trained by the principal investigator on the study protocol, ethical considerations and using the FGD interview guide. The FGD guide is presented in the online supplemental file. The fieldwork team comprised six researchers (three male and three female), with each site being attended by a male and a female researcher to encourage open dialogue.

Supplemental material

Ensuring accuracy and safety in FGDs

The FGDs were conducted in a community building, such as a community hall, to facilitate a comfortable and familiar setting for participants while adhering to necessary social distancing measures. An audio recorder was strategically positioned to ensure all participants’ inputs were captured, maintaining their safety throughout the discussions. These FGDs were conducted in Krio, a widely spoken local language, with only researchers and participants present, fostering an environment of trust and openness. Participants received a bottle of soft drink and a packet of biscuits following the FGDs.

Data analysis

After the FGDs, the six researchers reviewed their notes and recordings to confirm completeness. Subsequently, translations and transcriptions from Krio to English were handled carefully to preserve linguistic nuances and cultural context. One researcher and the principal investigator performed thematic analysis using an open coding approach and NVivo V.12 software, allowing the team to identify themes emerging directly from the data inductively. This approach was complemented by our preparatory work informed by the insights of Enria and Tengbeh, (unpublished), 2020 and the SCT framework, which guided the identification of key themes related to observational learning, trusted sources and behavioural outcomes. One researcher and the principal investigator conducted the coding process to enhance reliability, followed by a collaborative review to reconcile discrepancies and ensure a robust, consistent thematic framework. This method enabled a nuanced understanding of the data, aligning with the SCT framework by uncovering patterns within the adolescents’ responses that reflect their information-processing strategies and the influence of sociocultural contexts on their health-related decisions and actions.

Patient and public involvement

None.

Results

Our study included 16 FGDs (with a total of 86 participants). It was conducted in three distinct localities: Murray Town in Western Area (urban) (27 participants), Waterloo (peri-urban) (27 participants) and Gbo chiefdoms in Bo district (rural) (32 participants). All participants completed the study. These FGDs lasted an average of 86 min (SD±11 min).

We have structured our findings into four thematic categories:

  1. Informational sources and cognitive processing examines adolescents’ navigation and appraisal of health information sources.

  2. Understanding COVID-19, focusing on adolescents’ conceptualisations of the origin and causes of the virus.

  3. Behavioural responses to COVID-19, discussing how perceptions of risk and knowledge of preventive measures guided health-related behaviours.

  4. Social influences on health perceptions, exploring the impact of societal and observational influences, including perceptions of health workers, on adolescents’ health beliefs and actions.

This structure allows for an exploration of the interplay between personal beliefs, societal influences and behavioural responses within the context of the pandemic.

Informational sources and cognitive processing

Adolescent girls identified various health information sources, including schools, social media, friends, community sensitisation, parents, other family members, radio, health workers, television and local markets. While schools were an important information source in urban areas, their significance diminished in peri-urban and rural settings.

Girls in urban environments expressed trust in health workers, teachers and close family members, valuing their knowledge and concern for their welfare. However, scepticism was noted towards family members perceived as withholding information, encapsulated by one girl’s observation: ‘If I ask them about HIV, they won’t say you get it from sex. Instead, they will say you get it when you have a lot of friends’. Conversely, social media and neighbours were often deemed unreliable, labelled ‘Den Say’ (hearsay) and ‘Congosa’ (gossip). Notably absent in the urban discourse is the mention of ‘chiefs’, a role replaced by ‘headmen’ in these settings. Headmen, while present, hold diminished significance in urban areas characterised by urban migrants of diverse ethnic origins, leading to a greater reliance on formal government and legal systems.

Radio emerged as the most trusted source in peri-urban areas, believed to disseminate government-verified information. Some girls also reported trusting some relatives and chiefs. As with girls in the urban setting, similar distrust was shown towards social media, with one girl recounting: ‘I don’t believe social media. The last time they came with a message that they would be spraying during lockdown…that brought serious panic for us. From then on, I haven’t believed in social media’.

Rural adolescents primarily trusted health workers and radio. They did not trust information from community members and peers at the stream while doing their laundry, at the public tap when fetching water, on the farm or in informal conversations in their church groups. Some reported not trusting the chief and preferring what they believed to be verified information from the radio, while others reported trusting the chief. This group distrusted family and friends the most compared with those in the urban and peri-urban areas. They also did not trust social media, citing Facebook and WhatsApp as untrustworthy. Trust in health workers was underscored by direct quotes affirming their care and the improbability of them causing harm, ‘Not true, they care for the sick people’, and personal experiences confirming safety, ‘[Not true], Because my brother went for treatment at the hospital, he came back, and nothing happened to him’.

Understanding COVID-19

In urban settings, some believe COVID-19 is ‘man-made’, citing its emergence from China and associations with consumption of bats: ‘Yes, [it is man-made] because it is a virus and anything that is a virus cannot be made by God’. In contrast, others see it as divine retribution: ‘I believe it’s God because we humans have done a lot of wrong things against God’. The consensus across all groups dismisses witchcraft as a cause, underlining a rational approach to understanding the pandemic: ‘No. Witches and wizards…they too fear contracting it’. These views encapsulate the complex interplay of cultural, educational and spiritual influences shaping adolescent perspectives on COVID-19.

The discussion around vulnerability to COVID-19 among adolescents also sheds light on their capacity to challenge and reconsider misconceptions. Most participants rejected the notion that the virus could not affect black people, using local cases and the universal nature of viruses and death as counterarguments. For instance, an urban participant pointed out, ‘[I disagree] because the first person that was affected in Sierra Leone was black, and so I think black people can be affected by the virus’. This assertion, alongside others, underscores a critical engagement with misinformation driven by personal experiences, societal observations and trust in authoritative health figures.

Behavioural responses to COVID-19: preventive measures, perceived risks and treatment options

Adolescents in rural settings shared a common belief in the efficacy of environmental factors, such as heat, in combating the virus, with one participant noting, ‘[I agree] because, in the white man’s countries, [the] death toll is higher than in Africa’. This perception underscores a contextual understanding of the spread of the virus, influenced by global observations and local environmental comparisons. However, this view was not universally accepted, with some participants raising concerns about the potential for heat to facilitate virus transmission through sweat, an idea possibly conflated with their knowledge of Ebola: ‘[I disagree] because like we are sitting here if someone’s sweat rubs on my skin it will transfer the Corona?’ and ‘[I disagree] there is heat in the country, yet still people are dying of Corona’. These statements highlight the complexity of adolescents’ risk assessments, influenced by a mix of accurate information, misconceptions and the application of logic derived from past health crises.

Regarding treatment options, there was a discernible preference for clinical medicine over traditional or spiritual interventions, with a rural participant stating, “No. If I am ill, I will go to the doctor for treatment and not to a pastor since they are not medical personnel”. This preference illustrates a reliance on formal healthcare systems despite the presence of traditional and religious beliefs within the community. Yet, the role of faith was not entirely dismissed, as indicated by a peri-urban adolescent’s belief in the complementary nature of prayer and medicine: ‘I disagree. Although prayer can cure sick [illness], I heard that a pastor from Nigeria contracted the sick [illness] in China. But I believe good prayer can heal the sick. Prayer helps a lot. Treatment also helps when you are sick [ill]’.

These quotes from participants vividly illustrate the multifaceted nature of adolescents’ responses, reflecting a blend of modern and traditional beliefs, the impact of global narratives on local perceptions, and the critical role of education in shaping health behaviours.

Social influences on health perceptions and health workers

The perceptions and attitudes towards health workers among adolescent girls in Sierra Leone reflect a complex interplay of trust, societal influences and personal experiences. Generally, the consensus among the participants was a firm disagreement with the notion that health workers could intentionally harm patients or contribute to the spread of COVID-19. This trust is rooted in personal narratives and observations, such as one urban participant’s assertion, ‘Nurses are good ….My uncle was treated in the hospital and returned home without any problem’. Such statements highlight a foundational belief in the benevolence and professionalism of health workers, further supported by the recognition of their vulnerability to the virus, as noted by a peri-urban participant: ‘Not true they also become infected’.

This trust in health workers contrasts sharply with broader societal scepticism about the virus. Despite widespread misinformation and disinformation, adolescents dismissed the idea that COVID-19 is a fabrication, citing media reports and governmental actions as concrete evidence of its reality. The closure of schools and places of worship was particularly persuasive, with one peri-urban participant remarking, ‘I disagree. Corona is real because if Corona is not real, they would not have closed schools, mosques, and churches’.

These narratives reveal the significant role social interactions and observations play in shaping adolescents’ perceptions of health workers and their attitudes towards COVID-19. The trust and confidence placed in health workers, in the backdrop of a global health crisis, illustrate the critical role of healthcare professionals as providers of medical care and as pillars of stability and trust within their communities.

Discussion

This study of how information was navigated by adolescent girls in Sierra Leone amidst the COVID-19 pandemic reveals a complex interplay of trust, societal norms, past experiences with Ebola and personal beliefs. The thematic approach used in this paper provides a lens through which to understand these dynamics.

In Sierra Leone, adolescent girls access health information through various channels, including schools, social media, family, health workers, radio and community initiatives. While these sources align with global trends, notable differences emerge. For instance, unlike in Iran, where mothers and same-sex friends are primary sources,18 and books serve as a significant medium, such preferences were not observed in Sierra Leone. Contrary to the heavy reliance on internet search engines in the UK and the USA,19 such usage was minimal among adolescents in Sierra Leone. Furthermore, while Croatian adolescents view their parents as reliable sources,20 this study found a more diverse trust spectrum in Sierra Leone. These variations could stem from cultural, socioeconomic and educational differences, disparities in access to technology and the influence of community structures unique to each region.

The prominence of schools as a primary source in urban areas highlights the role of educational institutions in disseminating health information. However, the significance of schools as information sources diminished in peri-urban and rural settings, where radio and health workers became more central. This shift underscores the importance of accessible and reliable information channels that can reach adolescents across different geographical and social contexts. The critical engagement with social media and informal networks, often labelled as ‘Den Say’ (hearsay) and ‘Congosa’ (gossip), points to a discerning approach towards evaluating the trustworthiness of information. Adolescents’ scepticism towards these less formal sources reflects a broader awareness of the potential for misinformation and disinformation and the value placed on verified knowledge, especially in health matters. Societal norms, personal experiences and the perceived authority of the information source deeply influence the cognitive processing involved in navigating information sources. Adolescents demonstrate a nuanced understanding of trustworthiness, often balancing traditional beliefs with modern medical advice. The reliance on health workers and formal communication channels, such as radio, indicates a preference for sources that are perceived as credible and authoritative. This is a remarkable finding since the distrust of the health system during the Ebola emergency occurred only 5 years previously.12

The beliefs surrounding the origins of COVID-19 among adolescents in Sierra Leone are varied, reflecting a blend of scientific understanding and cultural interpretations. Some adolescents in urban settings articulated the belief that COVID-19 is ‘man-made’, possibly influenced by global narratives and the extensive dissemination of information through digital platforms. This belief contrasts with others who view the pandemic as divine retribution, suggesting that spiritual and moral frameworks significantly influence their understanding of the virus. Such diverse perspectives highlight the need for public health communications to address and clarify misconceptions about the origins of the virus, ensuring that messages are culturally sensitive and scientifically accurate. Comparatively, beliefs about the origin of COVID-19 and preventive measures among adolescents in Sierra Leone reflect a broader spectrum of misconceptions and cultural interpretations documented globally. Research from the USA to sub-Saharan Africa reports similar myths and cultural beliefs, illustrating a worldwide challenge in aligning public perceptions with scientific evidence.21 22

Preventive measures and beliefs about COVID-19 among adolescents showcase a complex interplay between knowledge, cultural practices and personal experiences. For instance, the belief that environmental factors, such as heat, could impact the spread of the virus indicates an attempt to correlate local environmental conditions with global pandemic trends. However, some adolescents expressed scepticism towards this belief, citing concerns that contradict their understanding of virus transmission, such as the fear that sweat could facilitate the spread of COVID-19, a belief likely influenced by their experiences with previous health crises like Ebola. These discussions about prevention also extend to treatment options, where there’s a clear preference for clinical medicine over traditional or spiritual remedies among most adolescents. Yet, the role of faith and prayer in coping with illness underscores a significant cultural dimension in health behaviour, illustrating that spiritual beliefs continue to influence adolescents’ responses to health crises.

Our findings underscore the importance of addressing the multifaceted beliefs and misconceptions about the pandemic among adolescent populations. They highlight the critical role of education and public health messaging in dispelling myths and promoting scientifically grounded understandings of the virus. The need for adequate health communication strategies is highlighted as a lesson for the future by the Lancet COVID-19 Commission.23 Tailoring these messages to be culturally relevant and accessible is essential for fostering effective preventive behaviours and building resilience against misinformation. Our findings emphasise the need for ongoing dialogue between public health officials, educators and communities to ensure that adolescents are equipped with accurate information to navigate the challenges posed by COVID-19 and future health crises.

Our findings reveal a conscientious engagement with recommended preventive measures among adolescents, driven by their understanding of COVID-19 transmission and efforts to mitigate risk. Despite varying beliefs about the origins of the virus and the efficacy of certain preventive strategies, such as the debated role of environmental heat, adolescents demonstrated a pragmatic approach to health safety. For instance, the acceptance and practice of hand hygiene and social distancing reflect a widespread acknowledgement of their importance in preventing the spread of the virus, echoing global health recommendations. This behaviour underscores the critical role of accurate, accessible health information in empowering individuals to make informed decisions about their health.

Beliefs about sweat transmitting COVID-19 reflect a nuanced understanding of virus transmission, suggesting areas where educational efforts could enhance knowledge. While there is debate over sweat as a transmission vector, this belief underscores the importance of clear, targeted communication to clarify how COVID-19 spreads and to reinforce preventive measures. Engaging in ongoing education to bridge these knowledge gaps is crucial, ensuring that public health practices are based on accurate information and trust in scientific evidence is strengthened, as discussed by Agley and Xiao.21

The diverse views on treatment options, ranging from a strong preference for clinical medicine to a belief in the potential of prayer and traditional remedies, illustrate the multifaceted nature of health behaviours in the face of COVID-19. These preferences reflect personal and cultural beliefs and indicate a broader community dialogue about health, illness and healing. Encouraging open discussions and providing evidence-based information on treatment efficacy is crucial in aligning public health behaviours with best practices. The importance of open and transparent discussion in promoting positive behavioural responses to COVID-19 is acknowledged by Porat et al.24

The behavioural responses to COVID-19 among adolescent girls in Sierra Leone highlight the complex interplay between knowledge, beliefs and societal influences. Our findings emphasise the importance of tailored public health messaging that considers local cultural contexts, addresses misconceptions and reinforces the adoption of effective preventive measures. Building trust in health information sources, ensuring that messages are both culturally sensitive and scientifically accurate, and supporting health literacy is paramount for fostering positive behavioural responses.25 Engaging communities in these efforts, mainly through the involvement of trusted figures such as health workers, can enhance the impact of these messages and support positive health behaviours.26

The discerning responses to COVID-19 prevention and treatment among adolescents in Sierra Leone resonate with behavioural patterns identified in diverse cultural settings. This reflects a global narrative where official guidelines, cultural practices and individual beliefs converge to shape pandemic behaviours.27

The role of social interactions in shaping health perceptions, particularly health workers who experienced distrust during the Ebola outbreak, were widely trusted across all regions. Given appropriate interventions, this pivot signifies the transient nature of trust and the potential for its restoration. Radio and community sensitisation programmes received broad endorsement, with particular emphasis in peri-urban and rural locales. The elevated trust in these areas appeared tied to governmental trust, suggesting these platforms could be pivotal for public health campaigns. Urban regions presented a nuanced picture, indicating potential partnerships with other trusted entities. From SCT, trust in community messages can be construed as observational learning. Influenced by role models in their communities, adolescents develop trust in specific sources, underscoring the importance of involving local figures in health initiatives. The dynamic restoration of trust in health professionals, observed in our study, emphasises the importance of credible, empathetic health communication in rebuilding public confidence, a theme echoed in pandemic responses worldwide.

It is important to note that this study was conducted in July 2020, when COVID-19 vaccines were not yet available. The absence of vaccines likely shaped the discourse around prevention and treatment options, focusing on non-pharmaceutical interventions and community-based strategies. The subsequent introduction of vaccines has had a polarising effect on public opinion, introducing new dimensions to the conversations around trust, misinformation and compliance with health guidelines. This temporal context is crucial for interpreting our findings, as perceptions and behaviours may have evolved with the ongoing pandemic and the advent of vaccination campaigns. The prevaccine setting of this study captures a unique moment in the pandemic’s history, offering insights into the foundational beliefs and attitudes that later influenced vaccine acceptance and hesitancy. Other potential limitations of the study include the potential for bias due to self-reporting and sampling bias towards a specific subset of adolescents due to the recruitment method used.

This post was originally published on https://bmjopen.bmj.com