Reviewer #1: This manuscript addresses a highly relevant public health issue. Overall the manuscript is well-structured and presents important findings however, a few refinements could enhance clarity. Specifically, the discussion could be strengthened by drawing clearer implications for policy and scalability,how lessons from high-fidelity can be adapted to low fidelity settings. Adding explanatory footnotes to some of the tables and ensuring that figures and tables, supporting materials are properly referenced intext .
Reviewer #2: This manuscript addresses an important and understudied implementation science topic: implementation fidelity of tuberculosis (TB) screening among diabetes mellitus (DM) patients in routine care settings in Tanzania. The topic is relevant to TB–DM collaborative activities and aligns well with global priorities. However, several substantive issues need to be addressed before the findings can be interpreted with confidence.
Sampling strategy There is a lack of clarity and internal consistency between the sampling strategy described in the Methods and the way provider numbers are reported in the Results. The Methods indicate that 2–4 healthcare providers were selected per facility using proportional allocation and simple random sampling, yet Table 1 reports aggregate numbers by facility type (e.g., dispensary, health centre, hospital) without indicating how many providers were recruited from each of the 20 facilities. This makes it difficult to assess representativeness and raises concerns about clustering (e.g., whether multiple providers came from the same facility). The authors should clearly report the number of participants recruited per facility, ideally in a supplementary table, and explain how the stated sampling strategy was operationalised.
Outcome definition and interpretation The primary outcome is provider-level implementation fidelity, measured through self-reported adherence to TB screening guideline components. However, the Results and Discussion repeatedly imply patient-level screening coverage (e.g., statements suggesting that a certain proportion of DM patients were screened for TB). No patient-level numerator or denominator is presented, and the Methods do not describe record review or observation. The authors should consistently frame the outcome as provider-level fidelity, revise language that implies patient screening coverage, and explicitly acknowledge the absence of patient-level screening data as a limitation if such data were not collected.
Unsupported causal explanations The Discussion attributes low implementation fidelity (17%) to factors such as lack of integrated TB–DM training and provider role allocation, yet these explanations are not adequately supported by the study data. Training does not appear to remain significant in adjusted analyses, and several explanatory statements are not referenced. In addition, the Discussion suggests that degree-holding providers may focus on administrative duties, while the Methods state that staff in administrative roles were excluded from the study. These contradictions should be resolved, and causal language should be softened or removed where not directly supported by evidence.
Discussion focus The Discussion begins by restating the study’s aim and strengths rather than clearly summarising the key findings. Several paragraphs repeat results or focus heavily on comparisons with other studies, with limited interpretation of what the findings mean for the Ubungo or Tanzanian primary care context. The Discussion would be strengthened by focusing on (i) the most poorly implemented screening components, (ii) why dispensaries showed lower fidelity, and (iii) the implications for TB–DM integration, supervision, and training in similar settings.
Statistical reporting The analytical approach (modified Poisson regression) is appropriate for the outcome, but there appear to be potential reporting errors (e.g., confidence intervals in Table 4 where bounds appear inconsistent). These should be carefully checked. In addition, typographical errors (e.g., “modified poison regression”) should be corrected.
Limitations section The limitations are acknowledged; however, they could be more clearly framed from an implementation science perspective, including reliance on self-reported practices, absence of observational or record-based verification, and the cross-sectional design limiting causal inference.