Observational studyBMJ open2026
Research waste in total knee arthroplasty studies: an observational study on registered trials.
Observational study in BMJ open, 2026. The graph could read no effect estimate from its abstract, so it casts no vote on the map. Cited by 2 papers.
What it found
Each row is one number read from the abstract, on the scale the paper reported it, with its interval. Left of the dashed line favours the treatment, right favours the comparator. Under each row is the sentence it came from. New to these charts? A ten-minute tutorial.
The abstract states no effect estimate the extractor could read, or names no intervention and outcome on the map, so this paper lights no cell and moves no belief. It is still indexed, cited and linked below.
The trial behind it
Trials whose registry record cites this paper, or whose number appears in the abstract. A trial that started after this paper was published is citing it as background, not reporting it.
Neither the registry nor the abstract names a trial number. If this is a trial report, that itself is worth knowing.
Who cites it
2 citing papers in PubMed.
- Research waste in total knee arthroplasty studies: an observational study on registered trials.BMJ open · 2026Observational
- Characteristics and research waste of immunotherapy randomized clinical trials: a cross-sectional analysis.Frontiers in immunology · 2026Article
Corrections and comments
PubMed lists nothing against this paper. Absence here is not a guarantee, only a check that was made.
Authors and funding
4 authors.
Funding
No grant is acknowledged in the PubMed record.
Abstract
backgroundTimely publication of preregistered study outcomes is not self-evident. Discrepancies can lead to significant research waste.
objectivesTo assess timely (within 7 years) and consistent publication of preregistered primary outcomes and associated factors of total knee arthroplasty (TKA) studies registered between 2000 and 2017 over time.
designAn observational study. DATA SOURCES: ClinicalTrials.Gov, MEDLINE, Embase, Cochrane Library, Web of Science, PubMed and Google Scholar.
participantsRegistered TKA trials at ClinicalTrials.Gov between 2000 and 2017. DATA EXTRACTION AND SYNTHESIS: ClinicalTrials.Gov's required and optional data elements for registering a study and the preregistered and published primary outcome, defined as the outcome stated in the primary outcome field on ClinicalTrials.Gov. We used descriptive statistics, Kaplan-Meier curves and Cox regression analyses.
results1352 registered TKA (1072 interventional; 280 observational) studies were included, with 967 (811 interventional; 156 observational) unique references. Regarding the publication of preregistered primary outcomes within 7 years, the results for interventional trials were 0% (2000), which increased to 59.6% (2017). Observational studies were timely published in 0% (2000) and 37.5% (2017). Interventional trials and observational studies not funded by industry were more likely to have timely and consistent publication of their primary outcomes. Drug intervention trials were more likely to be timely and consistently published than procedure-focused trials. Phase 3 interventional trials were more likely, while phase 1 trials were less likely to be consistently published on time.
conclusionDespite ongoing efforts to improve publication rates, over a third of interventional trials remain unpublished within 7 years. For observational studies, the rate is even lower, with only two-fifths published on time, contributing to significant research waste. PROSPERO REGISTRATION NUMBER: CRD42021246599.
Indexed as
Identifiers
What OpenQuestion holds
Registered trials
Read under generation 80e0d062 · epoch 390. Bibliography from PubMed, PubMed Central and OpenAlex; grants from NIH RePORTER; trial links from ClinicalTrials.gov; estimates, votes and beliefs from the OpenQuestion graph.