The article by Lawrence Leung discusses the validity, reliability, and generalizability of qualitative research in the context of primary care. Qualitative research, which focuses on understanding patterns and richness in non-numerical data, has significant contributions to primary care, particularly in areas such as health screening, disease monitoring, and policy evaluation. The author highlights five studies that illustrate how qualitative methods have advanced primary healthcare, from mobile health technology for COPD management to national legislation for children's healthcare insurance. The article also addresses the challenges in assessing the quality and trustworthiness of qualitative research due to its subjective nature. It outlines various criteria for evaluating the quality of qualitative research, including methodology, interpretation, and systematicity. Key concepts such as validity, reliability, and generalizability are discussed, emphasizing the importance of appropriate tools, processes, and data in ensuring the validity of qualitative research. Reliability is defined as consistency in the research process and results, while generalizability is assessed through criteria like systematic sampling and triangulation. Despite these efforts, some researchers argue that qualitative research is inherently diverse and cannot be unified under a single system. The article concludes by reiterating that the three gold standards—validity, reliability, and generalizability—apply to both quantitative and qualitative research, but the nature and type of processes differ ontologically and epistemologically.The article by Lawrence Leung discusses the validity, reliability, and generalizability of qualitative research in the context of primary care. Qualitative research, which focuses on understanding patterns and richness in non-numerical data, has significant contributions to primary care, particularly in areas such as health screening, disease monitoring, and policy evaluation. The author highlights five studies that illustrate how qualitative methods have advanced primary healthcare, from mobile health technology for COPD management to national legislation for children's healthcare insurance. The article also addresses the challenges in assessing the quality and trustworthiness of qualitative research due to its subjective nature. It outlines various criteria for evaluating the quality of qualitative research, including methodology, interpretation, and systematicity. Key concepts such as validity, reliability, and generalizability are discussed, emphasizing the importance of appropriate tools, processes, and data in ensuring the validity of qualitative research. Reliability is defined as consistency in the research process and results, while generalizability is assessed through criteria like systematic sampling and triangulation. Despite these efforts, some researchers argue that qualitative research is inherently diverse and cannot be unified under a single system. The article concludes by reiterating that the three gold standards—validity, reliability, and generalizability—apply to both quantitative and qualitative research, but the nature and type of processes differ ontologically and epistemologically.