Proposed Title Determinants and Consequences of Patient and Health System Delays in Tuberculosis Diagnosis and Treatment Among Individuals Aged 15 Years and Above at Kenyatta National Hospital, Nairobi County, Kenya Abstract Background: Delayed tuberculosis (TB) diagnosis and treatment remain major public health challenges that undermine progress toward the WHO End TB Strategy. In tertiary hospitals, both patient-level and system-level delays can increase morbidity, mortality, and nosocomial …

BACKGROUND This study investigated the delays experienced by patients and healthcare systems in the diagnosis and treatment of tuberculosis (TB) among adults aged 15 years and above at Kenyatta National Hospital. Tuberculosis remains one of the leading infectious diseases globally, and timely diagnosis and initiation of treatment are crucial to reducing transmission, morbidity, and mortality. The study aimed to quantify the duration and determinants of both patient-related and healthcare system-related delays in accessing TB diagnosis and treatment services. OBJECTIVE The study aimed to quantify the duration and determinants of both patient-related and healthcare system-related delays in accessing TB diagnosis and treatment services. METHODS A mixed-methods design was employed, integrating quantitative data from patient records and qualitative interviews with healthcare providers. Patients with confirmed TB were recruited between January 2020 and December 2022. The study examined socio-demographic factors, health-seeking behaviors, diagnostic timelines, and healthcare service efficiency indicators. Quantitative data were analyzed using descriptive and inferential statistics, while qualitative data provided contextual insights into systemic challenges and patient experiences. RESULTS Findings revealed that the median patient delay—the time from symptom onset to first health-seeking—was significantly longer than the healthcare system delay—the time from first facility visit to diagnosis confirmation. Factors contributing to patient delay included low awareness of TB symptoms, self-medication, stigma, and economic barriers. On the other hand, healthcare system delays were associated with laboratory turnaround times, diagnostic capacity gaps, and referral inefficiencies. Gender, education level, and distance to health facilities were also found to significantly influence delay durations. CONCLUSIONS The study concluded that both patient and healthcare system factors contribute substantially to overall diagnostic and treatment delays. Addressing these challenges requires integrated interventions that strengthen TB awareness, improve laboratory infrastructure, enhance referral systems, and promote patient-centered care. Policymakers should prioritize targeted health education, community screening, and investment in rapid diagnostic technologies to accelerate TB case detection and treatment initiation. CLINICALTRIAL Trial Registration: This study was reviewed and approved by the Mount Kenya University Institutional Review Board (MKU-IRB) under reference MKU/ERC/PH/127/2020, and subsequently authorized by the National Commission for Science, Technology and Innovation (NACOSTI) under permit number NACOSTI/P/21/9874. As this was a retrospective, observational study using existing patient data and facility-level records, it was not registered as a clinical trial.