{"doi":"10.1111/jgs.70202","title":"Reply to: Comment on: Agreement Between Fingerstick Blood Glucose and Continuous Glucose Monitor Measures Among Long‐Term Care Facility Residents","abstract":"We thank Dr. Song for their thoughtful and constructive letter, “Comment on: Agreement Between Fingerstick Blood Glucose and Continuous Glucose Monitor Measures Among Long-Term Care Facility Residents” about our article [1]. We appreciate their attention to this critical issue of hypoglycemia under-detection in long-term care facilities (LTCFs) and concur with their call to revise current glucose monitoring practices to advance patient care and safety. Below, we address Dr. Song's comments and reference our prior letter for additional context on the points raised [2]. We agree with Dr. Song's sentiments about the importance of transparent reporting in observational studies, particularly disclosing the basis for inclusion and exclusion criteria, and describing any informative patterns of missing data. In reporting our findings, we adhered to the guidelines on linking data in pharmacoepidemiology and observational research [3, 4]. As delineated in our article, residents in Cohort 1 who generated continuous glucose monitoring (CGM) readings were matched to their corresponding records in the Long-Term Care Data Cooperative (LTCDC) using the date of birth, sex, LTCF name, zip code, state, and calendar day of the glucose measurements [1]. Of the 9 residents, 5 could be connected to the LTCDC electronic health records (EHRs). Among those connected, 3 residents were dropped for lacking CGM and fingerstick blood glucose (FBG) measures on the same days. To facilitate a valid comparison, it was crucial to keep only residents who had both CGM and LTCDC glucose measures. Any absence of same-day CGM-FBG measures reflects logistical and clinical factors such as variability in residents' daily care schedules, instances when FBG tests were delayed because glucose values were recently obtained or residents were asleep, periods when CGM sensors were temporarily removed, or differences in timing between routine CGM readings and FBG testing, rather than investigator exclusion of data. We recognize that the small size of Cohort 1 may have reduced the generalizability of our findings. Accordingly, we analyzed a relatively larger sample of residents in Cohort 2, for whom both CGM and FBG data were directly available, thereby circumventing the data-linkage limitations encountered in Cohort 1, where 4 out of 9 (44%) of the residents without successful linkage to the LTCDC data were necessarily excluded. The findings from both cohorts were largely consistent, lending credibility to the main conclusion: FBG fails to capture a significant proportion of hypoglycemia events compared to CGM. We emphasize that including a second, larger cohort does not eliminate issues around external validity; rather, it mitigates the issue, thereby strengthening the clinical interpretation and relevance of our findings. As we described more fully in our previous correspondence [5], we encourage future researchers to study more heterogeneous LTCF populations to enhance the generalizability of results. Sampling a diverse array of LTCFs is also important since there is facility-level variation in glucose monitoring practices, including the timing of FBG checks and hypoglycemia response protocols, which could influence the detection of hypoglycemia. Finally, we agree with Dr. Song that variation in FBG meter models can affect measurement accuracy and limit generalizability. This further underscores the advantage of CGM, which provides continuous glucose data rather than a single reading and offers a more complete and reliable picture of glycemic control. Based on our findings, reliance on EHR-based FBG data alone can lead to many undetected hypoglycemia events, and consequently, missed opportunities to de-intensify glucose-lowering therapy and prevent harmful outcomes. Although current LTCF glucose monitoring relies almost exclusively on FBG testing, our study adds to a growing body of evidence that CGM is a valuable emerging technology that could improve hypoglycemia detection","journal":"Journal of the American Geriatrics Society","year":2025,"id":581755,"datarank":0.0,"base_score":0.0,"endowment":0.0,"self_citation_contribution":0.0,"citation_network_contribution":0.0,"self_endowment_contribution":0.0,"citer_contribution":0.0,"corpus_percentile":null,"corpus_rank":null,"citation_count":0,"citer_count":0,"citers_with_citation_signal":0,"citers_with_endowment":0,"datacite_reuse_total":0,"is_dataset":false,"is_dataset_confidence":0.961,"is_data_producer":false,"deposit_databanks":null,"is_oa":true,"file_count":0,"downloads":0,"has_version_chain":false,"published_date":"2025-01-01","fair_score":null,"fair_percentile":null,"algorithm_id":"datarank_citation_only_1hop_v6","ranking_scope":"data_only","authors":[{"id":280964,"name":"Medha Munshi","orcid":"0000-0001-6917-4197","position":1,"is_corresponding":false},{"id":312343,"name":"Christine Slyne","orcid":"0000-0002-3304-6510","position":2,"is_corresponding":false},{"id":266058,"name":"Nina R. 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