John H Powers

Dr. John H Powers

orcid

Research Focus & Metrics

Academic Career Length

21Years (2006-Present)

(Calculated once Scilit publication data is synced: current year − year of first publication + 1)

Representative Publications

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1 December 2015 in BMC Infectious Diseases
Verified
Journal Article
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JPJohn H Powers
John H Powers
MGM. Lourdes Guerrero
M. Lourdes Guerrero
NLNancy Kline Leidy
Nancy Kline Leidy
MFMary P. Fairchok
Mary P. Fairchok
ARAlice Rosenberg
Alice Rosenberg
GRGuillermo M. Ruiz-Palacios
Guillermo M. Ruiz-Palacios
To develop content validity of a comprehensive patient-reported outcome (PRO) measure following current best scientific methodology to standardize assessment of influenza (flu) symptoms in clinical research. Stage I (Concept Elicitation): 1:1 telephone interviews with influenza-positive adults (≥18 years) in the US and Mexico within 7 days of diagnosis. Participants described symptom type, character, severity, and duration. Content analysis identified themes and developed the draft Flu-PRO instrument. Stage II (Cognitive Interviewing): The Flu-PRO was administered to a unique set of influenza-positive adults within 14 days of diagnosis; telephone interviews addressed completeness, respondent interpretation of items and ease of use. Samples: Stage I: N = 46 adults (16 US, 30 Mexico); mean (SD) age: 38 (19), 39 (14) years; % female: 56 %, 73 %; race: 69 % White, 97 % Mestizo. Stage II: N = 34 adults (12 US, 22 Mexico); age: 37 (14), 39 (11) years; % female: 50 %, 50 %; race: 58 % White, 100 % Mestizo. Symptoms: Symptoms identified by >50 %: coughing, weak or tired, throat symptoms, congestion, headache, weakness, sweating, chills, general discomfort, runny nose, chest (trouble breathing), difficulty sleeping, and body aches or pains. No new content was uncovered during Stage II; participants easily understood the instrument. Results show the 37-item Flu-PRO is a content valid measure of influenza symptoms in adults with a confirmed diagnosis of influenza. Research is underway to evaluate the suitability of the instrument for children and adolescents. This work can form the basis for future quantitative tests of reliability, validity, and responsiveness to evaluate the measurement properties of Flu-PRO for use in clinical trials and epidemiology studies.

18 June 2012 in Statistics in Medicine
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Journal Article
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TFThomas R. Fleming
Thomas R. Fleming
JPJohn H Powers
John H Powers

1 September 2021 in Annals of Internal Medicine
Verified
Journal Article
Open access
SKSameer S. Kadri
Sameer S. Kadri
JSJunfeng Sun
Junfeng Sun
ALAlexander Lawandi
Alexander Lawandi
JSJeffrey R. Strich
Jeffrey R. Strich
LBLindsay M. Busch
Lindsay M. Busch
SWSarah Warner
Sarah Warner
The effect of surges in COVID-19 caseload on COVID-19 survival rates is unclear, especially independent of temporal changes in survival. This retrospective cohort study used data from a large U.S. ... Visual Association Between Caseload Surge and COVID-19 Survival in U.S. Hospitals. The effect of surges in COVID-19 caseload on COVID-19 survival rates is unclear, especially independent o... Background: Several U.S. hospitals had surges in COVID-19 caseload, but their effect on COVID-19 survival rates remains unclear, especially independent of temporal changes in survival. Objective: T...

1 January 2017 in Value in Health
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Journal Article
Closed access
JPJohn H Powers
John H Powers
DPDonald L. Patrick
Donald L. Patrick
MWMarc K. Walton
Marc K. Walton
PMPatrick Marquis
Patrick Marquis
SCStefan Cano
Stefan Cano
LBLaurie B. Burke
Laurie B. Burke

22 March 2018 in PLOS ONE
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Journal Article
Open access
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JPJohn H Powers
John H Powers
EBElizabeth D Bacci
Elizabeth D Bacci
NLNancy K Leidy
Nancy K Leidy
JPJiat-Ling Poon
Jiat-Ling Poon
SSSonja Stringer
Sonja Stringer
MGM Lourdes Guerrero
M Lourdes Guerrero
The inFLUenza Patient Reported Outcome (FLU-PRO) measure is a daily diary assessing signs/symptoms of influenza across six body systems: Nose, Throat, Eyes, Chest/Respiratory, Gastrointestinal, Body/Systemic, developed and tested in adults with influenza. This study tested the reliability, validity, and responsiveness of FLU-PRO scores in adults with influenza-like illness (ILI). Data from the prospective, observational study used to develop and test the FLU-PRO in influenza virus positive patients were analyzed. Adults (≥18 years) presenting with influenza symptoms in outpatient settings in the US, UK, Mexico, and South America were enrolled, tested for influenza virus, and asked to complete the 37-item draft FLU-PRO daily for up to 14-days. Analyses were performed on data from patients testing negative. Reliability of the final, 32-item FLU-PRO was estimated using Cronbach’s alpha (α; Day 1) and intraclass correlation coefficients (ICC; 2-day reproducibility). Convergent and known-groups validity were assessed using patient global assessments of influenza severity (PGA). Patient report of return to usual health was used to assess responsiveness (Day 1–7). The analytical sample included 220 ILI patients (mean age = 39.3, 64.1% female, 88.6% white). Sixty-one (28%) were hospitalized at some point in their illness. Internal consistency reliability (α) of FLU-PRO Total score was 0.90 and ranged from 0.72–0.86 for domain scores. Reproducibility (Day 1–2) was 0.64 for Total, ranging from 0.46–0.78 for domain scores. Day 1 FLU-PRO scores correlated (≥0.30) with the PGA (except Gastrointestinal) and were significantly different across PGA severity groups (Total: F = 81.7, p<0.001; subscales: F = 6.9–62.2; p<0.01). Mean score improvements Day 1–7 were significantly greater in patients reporting return to usual health compared with those who did not (p<0.05, Total and subscales, except Gastrointestinal and Eyes). Results suggest FLU-PRO scores are reliable, valid, and responsive in adults with influenza-like illness.

1 February 2018 in Value in Health
Verified
Journal Article
Closed access
JPJohn H Powers
John H Powers
EBElizabeth D. Bacci
Elizabeth D. Bacci
MGM. Lourdes Guerrero
M. Lourdes Guerrero
NLNancy Kline Leidy
Nancy Kline Leidy
SSSonja Stringer
Sonja Stringer
GRGuillermo M. Ruiz-Palacios
Guillermo M. Ruiz-Palacios