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Real-World Evidence Generation
Published in Kelly H. Zou, Lobna A. Salem, Amrit Ray, Real-World Evidence in a Patient-Centric Digital Era, 2023
Joseph S. Imperato, Joseph P. Cook, Diana Morgenstern, Kim Gilchrist, Tarek A. Hassan, Jorge Saenz, Danute Ducinskiene
In contrast, observational study is a type of study in which individuals are observed or certain outcomes are measured (National Cancer Instittue, 2022). No attempt is made to affect the outcome (for example, no treatment is given.) As such, observational data are the essence of “real world.” Observational studies are non-experimental in nature, and thus their role and validity has been a controversial topic in the literature (Collins and Bowman 2020). Nonetheless, observation-based studies can suggest important areas for RCTs, hypothesis generation or clarify our understanding of patient experience. They can do so by utilizing various designs including case report or case series, ecologic, cross-sectional (i.e., a prevalence study), case-control and cohort studies (Kumar and Khan 2014).
Etiological explanations
Published in Olaf Dammann, Etiological Explanations, 2020
The notion of “quasi-intervention” concerns analytical data manipulation in observational (noninterventional) studies. It builds on the notion that an ideal observational study with sufficient statistical power, well-defined groups of participants, collection of high-quality data, inclusion of all known confounders, and exclusion of all known biases should not be considered epistemologically inferior to a randomized trial. The results of a perfect observational study should come rather close to those of a randomized trial. For example, if taking a certain drug has a particular effect on clinical improvement in an ideal observational study, the results should be similar to those an RCT would provide. Obviously, it is easy to raise the objection that perfect studies do not exist. However, two data-manipulation techniques, propensity score adjustment and Mendelian randomization can bring observational study very close to the ideal, thereby contributing to the causal inference part of etiological explanations. A third technique, data stratification, is used to explore a phenomenon called effect modification, the observation that effect sizes differ in subgroups of the original study population, indicating that the variable that defines the subgroups must play some kind of mechanistic role in disease etiology.
Preliminaries
Published in Anastasios A. Tsiatis, Marie Davidian, Shannon T. Holloway, Eric B. Laber, Dynamic Treatment Regimes, 2019
Anastasios A. Tsiatis, Marie Davidian, Shannon T. Holloway, Eric B. Laber
In an observational study, individuals are not assigned treatment via randomization according to some experimental design, but rather receive treatment according to physician discretion or their own choice. In some situations, it may be unethical to conduct a randomized study; for example, it would be unacceptable to undertake a study randomizing participants to smoking or not. Thus, it is of interest to consider whether or not it is possible to estimate the average causal treatment effect δ*from the data from such a study and under what conditions.
Treatment retention and reductions in blood alcohol concentration (BAC) during the first 90 days of a telehealth program for alcohol use disorder
Published in The American Journal of Drug and Alcohol Abuse, 2023
Kevin A. Hallgren, Gantt P. Galloway, Katie Witkiewitz, Paul Linde, Bob Nix, John E. Mendelson
The current study has important limitations. Notably, it was an observational study without randomization or a control group; therefore, we could not test the efficacy of the treatment program against a control condition. Additionally, the data were originally collected for clinical care (rather than for research) which resulted in missing data for BAC, gender, and drinking goal for some patients. BAC data were increasingly unavailable as patients got further into treatment, and the treatment procedures did not include steps to verify that BAC readings were submitted by identified patients. Because BAC data collection was contingent on being in treatment, we could not validly estimate BAC trajectories for patients without 90-day treatment retention. We did not have access to structured measures of race, geographical location, health insurance, education, employment or other comorbidities for the current research. All patients had to have access to technology required for telehealth, and therefore results may not generalize to other patients without such access; notably, however, smartphone ownership in the United States continues to rise with 85% of US adults owning smartphones as of February 2021 (28).
The prevalence of oropharyngeal dysphagia in patients with chronic obstructive pulmonary disease: a systematic review and meta-analysis
Published in Expert Review of Respiratory Medicine, 2022
Wenyan Li, Mingjing Gao, Jin Liu, Fengwa Zhang, Rongjing Yuan, Qingling Su, Yetong Wang, Yanhong Wang
Observational study (cross-sectional studies, case-control studies, and cohort studies).The subjects were patients with COPD (Diagnostic criteria for the GOLD guidelines [11]: the presence of progressive dyspnea, chronic cough, and expectoration; A history of exposure to risk factors; Pulmonary function tests: FEV1/FVC < 0.7 after inhalation of bronchodilators suggests continued airflow limitation, among other conditions that can cause continued airflow limitation.Assess for oropharyngeal dysphagia.
Cut-off score of the Khalfa Hyperacusis Questionnaire with 10 selected items
Published in International Journal of Audiology, 2022
Hiroyuki Yamada, Toru Ishikawa, Naoki Oishi, Kaoru Ogawa
According to the Japan Ethical Guidelines for Medical and Health Research Involving Human Subjects, informed consent for the observational study was not required. We notified the research participants, or made public, the information concerning the research including the purpose of collection and utilisation of research information and stated that there was an opportunity to refuse participation or remove their data from the study after commencement. This information was also documented in each patient’s chart. The study was conducted abiding by the tenets of the Declaration of Helsinki and its later amendments and was approved by the ethics committee of the Keio University School of Medicine (20140242). All patients consented to the use of their data for future studies. Data were anonymised at the time of collection.