Trial reportInternational journal of clinical practice2008
The impact of analytic method on interpretation of outcomes in longitudinal clinical trials.
Trial report in International journal of clinical practice, 2008. The graph could read no effect estimate from its abstract, so it casts no vote on the map. Cited by 24 papers, 3 of them syntheses that pooled it.
What it found
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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
24 citing papers in PubMed, 3 syntheses or guidelines pooled it.
- Galantamine for dementia due to Alzheimer's disease and mild cognitive impairment.The Cochrane database of systematic reviews · 2024Pooled it
- Efficacy, tolerability, and safety of lurasidone for acute schizophrenia: A systematic review and network meta-analysis of phase 3 trials in Japan.Neuropsychopharmacology reports · 2020Pooled it
- Analgesic efficacy of opioids in chronic pain: recent meta-analyses.British journal of pharmacology · 2015Pooled it
- Body composition changes during weight reduction with tirzepatide in the SURMOUNT-1 study of adults with obesity or overweight.Diabetes, obesity & metabolism · 2025Trial
- Ixekizumab treatment and the impact on SF-36: results from three pivotal phase III randomised controlled trials in patients with moderate-to-severe plaque psoriasis.Quality of life research : an international journal of quality of life aspects of treatment, care and rehabilitation · 2020Trial
- A Randomized Clinical Trial of Oxytocin or Galantamine for the Treatment of Negative Symptoms and Cognitive Impairments in People With Schizophrenia.Journal of clinical psychopharmacology · 2017Trial
- Trial
- Add-on prolonged-release melatonin for cognitive function and sleep in mild to moderate Alzheimer's disease: a 6-month, randomized, placebo-controlled, multicenter trial.Clinical interventions in aging · 2014Trial
- Enhancing quality of life and mastery of informal caregivers of high-grade glioma patients: a randomized controlled trial.Journal of neuro-oncology · 2013Trial
- Self-Help for Depression via E-mail: A Randomised Controlled Trial of Effects on Depression and Self-Help Behaviour.PloS one · 2013Trial
- Post-treatment outcomes in a double-blind, randomized trial of sertraline for alcohol dependence.Alcoholism, clinical and experimental research · 2012Trial
- The Effect of Drug Holidays on Metacognitive and Theory of Mind Skills of Children Diagnosed with Attention Deficit Hyperactivity Disorder: Preliminary Findings.Neuropsychiatric disease and treatment · 2026Article
- Review
- PERSEUS 24-month analysis: a prospective non-interventional study to assess the effectiveness of intravitreal aflibercept in routine clinical practice in Germany in patients with neovascular age-related macular degeneration.Graefe's archive for clinical and experimental ophthalmology = Albrecht von Graefes Archiv fur klinische und experimentelle Ophthalmologie · 2021Article
- When can maximal efficacy occur with repeat botulinum toxin injection in upper limb spastic paresis?Brain communications · 2021Article
- Dose-Response Mixed Models for Repeated Measures - a New Method for Assessment of Dose-Response.Pharmaceutical research · 2020Article
- Evidence of unexplained discrepancies between planned and conducted statistical analyses: a review of randomised trials.BMC medicine · 2020Review
- Age-disparate partnerships and incident HIV infection in adolescent girls and young women in rural South Africa.AIDS (London, England) · 2019Article
- Clinical comparative effectiveness of acupuncture versus manual therapy treatment of lateral epicondylitis: feasibility randomized clinical trial.Pilot and feasibility studies · 2019Article
- A review of clinical treatment considerations of donepezil in severe Alzheimer's disease.CNS neuroscience & therapeutics · 2018Review
Corrections and comments
PubMed lists nothing against this paper. Absence here is not a guarantee, only a check that was made.
Authors and funding
3 authors.
Funding
No grant is acknowledged in the PubMed record.
Abstract
aimsVarious analytical strategies for addressing missing data in clinical trials are utilised in reporting study results. The most commonly used analytical methods include the last observation carried forward (LOCF), observed case (OC) and the mixed model for repeated measures (MMRM). Each method requires certain assumptions regarding the characteristics of the missing data. If the assumptions for any particular method are not valid, results from that method can be biased. Results based on these different analytical methods can, therefore, be inconsistent, thereby making interpretation of clinical study results confusing. In this investigation, we compare results from MMRM, LOCF and OC in order to illustrate the potential biases and problems in interpretation.
methodsData from an 8-month, double-blind, randomised, placebo-controlled (placebo; n = 137), outpatient depression clinical trial comparing a serotonin-noradrenalin reuptake inhibitor (SNRI; n = 273) with a selective serotonin reuptake inhibitor (SSRI; n = 274) were used. The study visit schedule included efficacy and safety assessments weekly to week 4, bi-weekly to week 8, and then monthly. Visitwise mean changes for the 17-item Hamilton Depression Rating Scale (HAMD(17)) Maier subscale (primary efficacy outcome), blood pressure, and body weight were analysed using LOCF, MMRM and OC.
resultsLast observation carried forward consistently underestimated within-group mean changes in efficacy (benefit) and safety (risk) for both drugs compared with MMRM, whereas OC tended to overestimate within-group changes.
conclusionsInferences are based on between-group comparisons. Therefore, whether or not underestimating (overestimating) within-group changes was conservative or anticonservative depended on the relative magnitude of the bias in each treatment and on whether within-group changes represented improvement or worsening. Preference should be given in analytic plans to methods whose assumptions are more likely to be valid rather than relying on a method based on the hope that its results, if biased, will be conservative.
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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.