Information need refers to the motivation to seek information that arises when individuals face an information gap or void (Wilson, 1981); it is the perceived discrepancy between the ideal and the actual state of one’s knowledge (Case & Given, 2016). However, prior literature has not reached a clear consensus on the core concept of information need (Case & Given).

Within a problem-oriented tradition, Taylor’s hierarchy of information need suggests that users’ expressed needs are fundamentally aimed at answering concrete questions (Taylor, 1968). According to Atkin (1973), Belkin et al. (1982), and Kuhlthau (1991), information needs originate in uncertainty which individuals attempt to reduce through information seeking. This uncertainty-centred view further explains the motivation behind information need. From Dervin’s sense-making perspective, information need is understood as a desire to ‘make sense of the situation’ when individuals, situated in specific spatiotemporal contexts, confront problems, concerns, or choices (Dervin & Naumer, 2009). The process is continuous and contextual, progressing from gap to bridge, with one information need triggering another in the same chain (Case & Given, 2016; Shenton & Dixon, 2004; Shenton & Gibson, 2011). Building on this, Cole (2011) further argues that from a knowledge-formation perspective, information need is a constructive process: it is problem driven and aims to generate new knowledge that is integrated into existing cognition. Accordingly, this study conceptualises information need as a dynamic process triggered by a perceived knowledge gap in a particular context and externally expressed through interrogative or help-seeking utterances.

Although a unified definition remains elusive, research increasingly highlights context as a key factor shaping information needs: the external information environment both shapes and constrains how needs are expressed and met (Dervin, 1998; Savolainen, 2007). This environment includes fields such as social media, online health communities, and physician-patient consultation platforms (Fisher, et al., 2004; Johnson, 2006), as well as the digital traces generated by individuals’ online activities. These traces can serve as temporal cues for retracing and reconstructing the trajectory of needs at different points in time (Chen, 2018; Cole et al., 2013).

To satisfy their information needs, individuals select from multiple information sources (Sonnenwald, 1999), and this selection is influenced by factors such as perceived source value, situational conditions, prior cognition, and usage experience (Kuhlthau, 1999; Savolainen, 2007). Platform-specific characteristics further affect how information needs are presented and what content is emphasised (Fisher, et al., 2004; Hirvonen, 2022; Park, et al., 2019). Understanding how individuals choose sources enables information providers to optimise service strategies, improve the efficiency of need–information matching, and better meet individuals’ information needs and access (Ingwersen & Järvelin, 2005; Savolainen, 2007; Wilson, 1999). Therefore, analyses of information need should be grounded in concrete contexts and platform attributes, and by integrating diverse media environments with digital traces, should probe more deeply into differences in expression and dynamic changes over time.

In the information age, various media platforms serve as key channels for information dissemination and social interaction. They influence how people living with HIV/AIDS express their information needs. Through diverse modes of communication, these platforms also provide avenues to access health information, share personal experiences, seek support, and engage in community activities (Aghaei, et.al., 2023).

Social media platforms offer people living with HIV/AIDS an efficient, real-time channel for obtaining information, enabling connection and interaction within their social networks (Genuis & Bronstein, 2017). They provide comprehensive medical information, including the latest research on HIV/AIDS, prevention measures, and treatment options (Genuis & Bronstein, 2017; Bazarova & Choi, 2014). Social media also provides emotional support (Bazarova & Choi, 2014), identity expression (Cunningham, et.al., 2018), and social interaction (McConnell, 2018), thereby helping to meet the diverse needs of people living with HIV/AIDS (Aghaei, et.al., 2023; Ibrahim, et.al., 2024).

Knowledge question-answer platforms, characterised by personalised recommendations and interactivity, address the specific information needs of people living with HIV/AIDS. The themes of expressed information needs on these platforms focus on individualised treatment information, such as treatment methods, medication selection, and side-effect management (UNAIDS, 2025).

Online health communities primarily supply the latest medical advice and professional treatment options, helping users understand treatment guidelines as well as the current health policies and research developments (Xu, et.al., 2023). Here, expressed information needs centre on diagnostic experiences, treatment approaches, and psychosocial support (Ayers, et.al., 2024).

Specialised forums dedicated to HIV/AIDS topics attract both healthcare professionals and people living with HIV/AIDS. They offer a space for exchanging experiences and obtaining insights into others’ treatment courses and outcomes, as well as enhancing personal empowerment (Bussone, et.al., 2017; Coulson & Buchanan, 2022). On these forums, most users frequently seek information on treatment methods and medication information, symptom and side-effect management, and post-diagnosis coping strategies (Boyce, et.al., 2022).

Therefore, the various media platforms have accumulated substantial data on the information needs expressed across the illness journey. The discrepancies in information environments, interactive dynamics, and content presentation modalities across different platforms significantly shape the ways these needs are articulated. Identifying and analysing these variations is essential for a deeper understanding of the genuine information needs of people living with HIV/AIDS, and for developing more precise and contextually relevant information services.

Information need themes refer to clusters of concerns repeatedly expressed in specific contexts that focus on particular information problems. These themes reflect both the focus of the content and the underlying need for information (Timmins, 2006). For people living with HIV/AIDS, such themes encompass knowledge of disease transmission, antiretroviral treatment, social support, and emotional adjustment, indicating an evolving attention to relevant information throughout illness management (Bekalu & Eggermont, 2013; Liu & Yuan, 2020). As individuals progress through the stages of the disease, their information needs change, becoming increasingly diverse and complex, and are influenced by multiple factors such as individual behaviour, the physical environment, and social context (Halman, et.al., 2013; Nokes & Nwakeze, 2005).

During the early stage of HIV infection, the information needs of people living with HIV/AIDS focus primarily on understanding basic disease knowledge, transmission routes, early symptom recognition, prevention, and treatment measures (Reid, et.al., 2010). Individuals at this stage are particularly concerned with information about HIV testing and urgently seek information on how to get tested and when to start treatment. As individuals move into the treatment stage, their information needs shift toward disease management, especially antiretroviral therapy monitoring and symptom relief (Reid, et.al., 2010). During this stage, they increasingly seek information on medical care, medication therapy, social work services, housing support, reproductive health, and overall disease management (Carter, et.al., 2019; Hernando, et.al., 2015; Lofgren, et.al., 2015; Reid, et.al., 2010). Although their understanding of treatment options and medication therapy improves, challenges remain in obtaining information on psychological support, emotional assistance and social services (Lofgren, et.al., 2015). In the later stages of infection, people living with HIV/AIDS confront more complex information needs involving multiple comorbidities, cognitive impairments, mental health issues, complex medication therapies and social isolation. Their needs centre on treatment methods, disease progression, cognitive function management, psychological support, social support, quality of life improvement and end-of-life care (Halman, et.al., 2013).

Although advances in HIV/AIDS treatment have extended life expectancy, the demand for comprehensive symptom management, psychosocial support and palliative care continues to increase, and existing treatment systems remain unable to fully meet these needs (Goodkin, et.al., 2018; Kanazawa, et.al., 2023; Karasz & Selwyn, 2003; Selwyn & Forstein, 2003). At every stage of the illness journey, people living with HIV/AIDS face social discrimination and stigma, creating a continual need for timely and accessible information and guidance related to psychological resilience and emotional well-being to help them cope with societal pressures (Odimegwu, et.al., 2017).

A comprehensive and systematic understanding of these stage-specific information needs not only enhances individuals’ ability to manage and cope with the disease but also fosters adaptation to life and social integration. Additionally, this understanding provides a practical foundation for developing personalised information services.

Due to the stigma and discrimination associated with the disease, people living with HIV/AIDS often seek related information anonymously through online media platforms (Aghaei, et.al., 2023). The functional roles and interactive features of different media platforms influence, to a significant extent, how people express their information needs and the priorities they place on them. This, in turn, results in distinct forms and content of information expression across various platforms (HIV.gov, 2025; Xu, et.al., 2023). A deeper understanding of these differences in information need themes across media platforms can enable more targeted and effective information provision, thereby enhancing the health management skills of people living with HIV/AIDS and improving their quality of life. Accordingly, this study posits the following research question:

Changes in personal life circumstances and routine behaviour often drive individuals to develop new information needs (Ruthven, 2022). As a chronic condition requiring long-term management, the information needs of people living with HIV/AIDS evolve dynamically and exhibit multidimensional characteristics across the various stages of the disease (Brashers, et.al., 2002). Because these needs evolve, providing personalised information tailored to their specific illness journey enhances their understanding and management of the condition and improves treatment adherence (Cao, et.al., 2020; Han, et.al., 2023; Marziali, et.al., 2021). A deeper examination of the dynamic evolution of information needs, particularly across different media platforms, will provide empirical support for the development of personalised information services for this population. Based on this, the second research question of this study is:

This study selected four platforms, namely Little Red Book (https://www.xiaohongshu.com), Baidu Knows (https://zhidao.baidu.com), Haodf.com (https://www.haodf.com), and the Zhi Ai Jiayuan forum (https://www.120x.net) as data sources. These platforms are important channels for people living with HIV/AIDS to express their information needs and obtain relevant information.

Data collection was completed using the Octopus Web-scraping software (https://www.octoparse.com), targeting posts published between 2022 and 2024. Because the social background during this period was relatively stable, the short-term impact of emergencies (such as epidemics) on information needs can be effectively reduced, thereby ensuring that the research focuses on long-term trends in information needs and their dynamic changes across the illness journey.

First, this study used ‘HIV’ and ‘AIDS’ as query terms to crawl relevant data. Second, to locate the information needs of people living with HIV/AIDS, this study employed interrogative and help-seeking markers as high-recall linguistic cues for an initial screening of the scraped corpus, including ‘what should I do’, ‘is it/are’, ‘seeking help’, ‘?’, ‘why’, ‘how’, ‘is there/any’, and ‘to ask’. These linguistic cues were used solely to identify sentence segments likely to contain information needs. They indicate the externalisation of a knowledge gap and an intention to seek solutions, thereby translating otherwise latent needs into operationalised questions (Belkin, 1982; Dervin & Naumer, 2009; Kuhlthau, 1991; Ruthven, 2019; Taylor, 1968).

The collected content included post titles, post details, publication time, and associated comments. Data were gathered from 26 September 2024 to 26 November 2024. In total, this study obtained 35,480 records from Little Red Book, 29,536 from Baidu Knows, 30,098 from Haodf.com, and 23,345 text records from the Zhi Ai Jiayuan forum. All data were drawn from publicly accessible pages; data collection and use strictly complied with each platform’s accessibility rules and terms of use. Following collection, de-identification procedures were implemented (for example, removal of usernames and or IDs, contact information, and geolocation) and no identification, contact, or intervention was undertaken at the individual level. The technical workflow of this study is presented in Figure 1.

In order to ensure the accuracy of the data, this study normalised the data from each platform after collection through data cleaning, selection, the removal of stop words, punctuation, numbers, and tokenisation.

By training the BERTopic model, this study identified thirty-six information need themes on Little Red Book, twenty-four themes on Baidu Knows, thirty-eight themes on the Haodf.com, and nineteen themes on the Zhi Ai Jiayuan forum. Based on the clustering results of the information need themes, these themes were grouped into fourteen categories: causation knowledge, pathology knowledge, scientific knowledge, social security, diet and health, fertility, future development, social interaction, treatment process, medication therapy, psychological issues, test results, diagnostic methods and surgery consultation. The information need themes and clustering results for each platform are shown in Table 4.

Based on the frequencies of information need themes across platforms, the chi-squared test indicated significant differences in theme distributions among platforms ( χ² = 39,396.98, df = 39, p < 0.001, Cramér’s V = 0.41). To further compare the proportional differences of specific themes across platforms, proportion z-tests were conducted for standardised comparisons. The results are presented in Table 5.

As shown in Table 5, the distribution of information need themes expressed by people living with HIV/AIDS varies significantly across media platforms. In particular, themes such as causation knowledge, pathology knowledge, scientific knowledge, social security, psychological issues, medication therapy, treatment process, and test results exhibit large inter-platform differences. In contrast, themes of fertility, diet and health, social interaction, diagnostic methods, future development and surgery consultation show smaller differences and relatively high consistency. On Little Red Book, people living with HIV/AIDS search for information on emotional support and social adaptation, especially peer-to-peer experience sharing. On Baidu Knows, their focus is on disease management and balancing everyday life, with a strong demand for pathology knowledge. On Haodf.com, they predominantly seek professional medical opinions and advice on treatment methods, medication efficacy, and complication management. Finally, on the Zhi Ai Jiayuan forum, their information needs centre on social security and related social support resources.

During the early stage of HIV infection (stage I), people living with HIV/AIDS express information needs related to social interaction, social security, pathology knowledge, scientific knowledge, psychological issues, and test results. During the middle stage of HIV infection (stage II), these themes become more diverse: they continue to seek social interaction, social security and scientific knowledge, but also search for information on diet and health, treatment process, medication therapy, fertility and future development. During the Advancing to AIDS stage (stage III), they continue to express needs for information on diet and health, treatment process and medication therapy, but in addition require pathology knowledge, scientific knowledge, test results, psychological issues, and surgery consultation. Figure 3 depicts the dynamic evolution of these information need themes across the stages of the disease.

The changes in information need themes of people living with HIV/AIDS during different disease stages across media platforms are illustrated in Figures 4–7.

On Little Red Book, people living with HIV/AIDS express different information needs during each stage of the disease. During the early stage of HIV infection (stage I), they primarily express different information need themes related to social interaction, pathology knowledge, scientific knowledge, psychological issues, and test results. During the middle stage of HIV infection (stage II), their information needs broaden to include social interaction, scientific knowledge, social security, fertility, diet and health, future development, treatment process, medication therapy, and diagnostic methods. During the Advancing to AIDS stage (stage III), their focus shifts markedly toward pathology knowledge, treatment process, diet and health, test results, psychological issues, and scientific knowledge, as shown in Figure 4.

On Baidu Knows, people living with HIV/AIDS during the early stage of HIV infection (stage I) search for social security, pathology knowledge, scientific knowledge, psychological issues, and test results. During the middle stage of HIV infection (stage II), in addition to ongoing interest in social security and scientific knowledge, their needs expand to include fertility, diet and health, treatment process, and medication therapy. During the Advancing to AIDS stage (stage III), their information needs become more concentrated on diet and health, treatment process, medication therapy, pathology knowledge, scientific knowledge, test results, and psychological issues, as shown in Figure 5.

On Haodf.com, people living with HIV/AIDS during the early stage of HIV infection (stage I) focus on causation knowledge, pathology knowledge, scientific knowledge, psychological issues, and test results. During the middle stage of HIV infection (stage II), their expressed needs shift to social security, fertility, treatment process, medication therapy, and diagnostic methods. During the Advancing to AIDS stage (stage III), their needs concentrate on treatment process, medication therapy, pathology knowledge, causation knowledge, scientific knowledge, psychological issues, and surgery consultation, as shown in Figure 6.

On the Zhi Ai Jiayuan forum, people living with HIV/AIDS during the early stage of HIV infection (stage I) express needs centred on social interaction, social security, pathology knowledge, scientific knowledge, and test results. During the middle stage of HIV infection (stage II), their information needs expand to include social interaction, social security, diet and health, treatment process, and medication therapy. During the Advancing to AIDS (stage III), their needs focus on diet and health, treatment process, pathology knowledge, scientific knowledge, and test results, as shown in Figure 7.

This study found significant differences among the themes of information needs expressed by people living with HIV/AIDS across various media platforms. These differences were closely related to each platform's functional positioning, information presentation style, and interactive mechanisms. Specifically, the Little Red Book platform is a lifestyle-oriented platform centred on visual and textual content and social interactions that encourages users to engage in emotional expression and exchange life experiences. Influenced by its social nature, people living with HIV/AIDS primarily express needs for social interaction-related information, including seeking a confidant, maintaining family and social relationships, and exchanging causation knowledge. This finding aligns with prior studies examining information needs expressed on social media platforms (Ayers, et.al., 2024; Jindal & Liao, 2018).

In contrast, Baidu Knows functions as a structured knowledge question-answer platform, leveraging its robust search capability to provide precise and practical solutions to specific problems (Bazrafshani, et.al., 2022). On this platform, people living with HIV/AIDS predominantly focus their information needs on causation knowledge, interpretation of test results, and social security issues. This differs from previously studied topics such as HIV virology, epidemiological trends, transmission routes, clinical diagnoses, and preventive measures (Liu & Yuan, 2020). These differences indicate that users on the Baidu Knows platform prefer information directly relevant and practically useful to their personal health situations. Their preference may stem from perceptions of Baidu’s search efficiency and information accuracy, positioning it as a preferred platform for obtaining practical and solution-oriented information.

Haodf.com, a professional medical service platform, emphasises content generated by healthcare professionals, including health articles and online consultations, thereby offering authoritative and specialised medical information (Liu & Lu, 2018). Previous research has shown that online health communities provide emotional support and social companionship for people living with HIV/AIDS (Liu & Yuan, 2020; Zhong, et.al., 2024). The findings from this study further illustrate that, owing to its strong emphasis on medical professionalism, users on the Haodf.com platform primarily express information need themes related to medication advice, medication efficacy, and management of complications.

Zhi Ai Jiayuan, a specialised forum for HIV/AIDS-related discussions, traditionally provides emotional and companionship support for users (Hu, 2018; Yu, 2015). This study further reveals that the platform has developed a more comprehensive organisational structure of information and content. Its content covers diverse aspects, including causation knowledge at the initial diagnosis, the treatment process, and medication therapy, to psychological issues, social security, diet and health, and fertility. With consistent topic continuity and strong community cohesion, the platform offers a stable information environment, enabling users to access comprehensive information spanning medical, daily life, and social dimensions. Thus, it constitutes an integrated information support system capable of meeting diverse needs across both disease stages and daily living.

Differences in how information needs are expressed stem from uncertainty within information behaviour and from individuals’ choices of information sources (Case & Given, 2016). When a knowledge gap is perceived, needs are typically voiced as questions or help-seeking requests and become progressively specified within concrete contexts (Belkin, 1982; Dervin & Naumer, 2009; Kuhlthau, 1991; Taylor, 1968). On this basis, individuals choose from multiple sources according to criteria such as relevance, timeliness, usability, and reliability (Kuhlthau, 1999; Sonnenwald, 1999; Wilson, 1999). Meanwhile, the affordances of different media also shape the modes of expression, and the relative weighting of information need themes (Hirvonen, 2022; Park, et al., 2019).

Across media platforms, the information services currently offered could be optimised based on the information need themes expressed by users on each platform. The Little Red Book meets the emotional support needs of people living with HIV/AIDS. However, to strengthen this, the platform could add dedicated columns such as Psychological Adjustment Guides and Patient Stories, encouraging users to share personal experiences via images, text, or short video. The Baidu Knows platform could refine platform tags and improve question categorisation by adding discussion areas for core themes such as Social security and Disease management. It may also consider establishing an Urgent help rapid-response mechanism to help patients find relevant solutions quickly. The Haodf.com platform could add specialised modules on Treatment effectiveness and Disease management, offering clear information on Treatment methods. Charts and flowcharts could help patients understand the treatment options across different disease stages. Lastly, the Zhi Ai Jiayuan forum could add dedicated sections on Treatment costs and Social security, providing detailed explanations of social security policies and cost-management guidelines. By setting up navigation tags for Insurance reimbursement or Financial assistance, the forum could ensure that users can find the existing social security resources to alleviate economic burdens.

This study indicates that people living with HIV/AIDS express information need themes that evolve over the course of their illness journey. These changes not only reflect how people adjust their information needs according to disease progression but also reflect the shifts in their daily routines. Different disease stages constitute key turning points in the illness journey (Genuis & Bronstein, 2017; Loveys, 1990). Prior to HIV infection, individuals’ lives correspond to the routine, controllable daily patterns described by Savolainen (1995).

An HIV diagnosis, however, represents a major life transition. To cope with this shift, people living with HIV/AIDS require information that meets their needs and maintains continuity in their daily lives. This aligns with previous findings that they need ongoing informational support to navigate the turning points of their illness journey (Brown & Powell-Cope, 1991; Han, et.al., 2023).

In the early stage of HIV infection (stage I), people living with HIV/AIDS experience physical discomfort and confusion due to the uncertainty surrounding diagnosis (Liu, et.al., 2023; Reid, et.al., 2010; Zhang, et.al., 2016). To alleviate this distress, they need scientific knowledge and pathology knowledge, as well as guidance for test result analysis, to build a preliminary understanding and reduce uncertainty. Simultaneously, the psychological burden of social stigma and related emotional stress drives a strong need for emotional support and counselling information. People living with HIV/AIDS seek resources on psychological counselling and social support to help them cope with emotional distress and adapt swiftly to the diagnosis.

Providing timely education on basic disease information, along with emotional comfort and reassurance, is therefore critical in helping individuals manage early-stage challenges and prepare for subsequent treatment.

During the middle stage of HIV infection (stage II), people living with HIV/AIDS have begun and adapted to standardised antiretroviral therapy and accumulated some experience in disease management (Supodo, 2020). At this point, the expressed information need themes shift from early-stage concerns to optimising treatment effectiveness. They increasingly seek information on medication precautions, medication efficacy, and personalised health management guidance based on treatment effectiveness. Such information enhances their disease management capacity, quality of life and strengthens their sense of control during long-term treatment, enabling more proactive lifestyle adjustments.

To adapt to new social and family roles, they also express needs for information and guidance on increasing social participation and protecting personal privacy in workplace and social settings (Goodman, et.al., 2022; Marellapudi, et.al., 2021). Interventions during the middle stage (stage II) should therefore align with these evolving information needs by promoting healthy lifestyles, fostering social engagement and supporting psychological adjustment, thereby enabling individuals to use information effectively to adapt to new environments and roles for long-term disease management.

As people progress to the Advancing to AIDS stage (stage III), people living with HIV/AIDS face more complex health challenges, including opportunistic infections and various complications. Their information needs become highly specialised and context-specific (Rangaraj, et.al., 2022; Zeng, et.al., 2025). They express needs for in-depth information on pathology, dietary and health recommendations, treatment effectiveness, and medication efficacy to manage their health, improve quality of life, and prolong survival. They also express needs for content on psychological adjustment, social support and palliative care to address emotional stress and relieve psychological burden, ensuring that social interaction and psychosocial needs are met (Zeng, et.al., 2025). Therefore, at this stage, people living with HIV/AIDS require personalised informational support that offers comprehensive medical guidance and holistic psychosocial assistance, guaranteeing that they receive adequate support and care in their final life phase.

Different media platforms possess distinct strengths in meeting these information needs. As the illness journey progresses, the uncertainty surrounding these needs is reconstructed in a stage-specific manner (Belkin, 1982; Dervin & Naumer, 2009; Kuhlthau, 1991; Ruthven, 2022). Accordingly, users are advised to select and adjust platforms in line with their current disease stage and the types of information required. During the early stage of HIV infection (stage I), they may prioritise Little Red Book for emotional expression and experience sharing. For concrete ‘how-to’ questions, Baidu Knows can provide structured answers, while Haodf.com offers physician advice and guidance when individualised medication or risk assessment are involved.

Upon entering the middle stage (stage II), people living with HIV/AIDS can combine Baidu Knows and Haodf.com to obtain actionable responses and verify knowledge to support treatment and daily life adjustments, while using Zhi Ai Jiayuan to supplement information on social security and provide peer support. During the Advancing to AIDS stage (stage III), they can focus their use on Haodf.com to obtain clinical decision making and referral recommendations, supplemented by Zhi Ai Jiayuan to provide social support and help build a sustainable support network. Table 6 further illustrates the relationships among information need themes, disease stages, and platform characteristics.