Timothy Walker

Timothy Walker


Research Focus & Metrics

Academic Career Length

11Years (2016-Present)

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

Representative Publications

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27 March 2018 in Implementation Science
Verified
Journal Article
Open access
PDF file
MFMaria Fernández
Maria Fernández
TWTimothy Walker
Timothy Walker
BWBryan J. Weiner
Bryan J. Weiner
WCWilliam A Calo
William A Calo
SLShuting Liang
Shuting Liang
MKMichelle C. Kegler
Michelle C. Kegler
Scientists and practitioners alike need reliable, valid measures of contextual factors that influence implementation. Yet, few existing measures demonstrate reliability or validity. To meet this need, we developed and assessed the psychometric properties of measures of several constructs within the Inner Setting domain of the Consolidated Framework for Implementation Research (CFIR). We searched the literature for existing measures for the 7 Inner Setting domain constructs (Culture Overall, Culture Stress, Culture Effort, Implementation Climate, Learning Climate, Leadership Engagement, and Available Resources). We adapted items for the healthcare context, pilot-tested the adapted measures in 4 Federally Qualified Health Centers (FQHCs), and implemented the revised measures in 78 FQHCs in the 7 states (N = 327 respondents) with a focus on colorectal cancer (CRC) screening practices. To psychometrically assess our measures, we conducted confirmatory factor analysis models (CFA; structural validity), assessed inter-item consistency (reliability), computed scale correlations (discriminant validity), and calculated inter-rater reliability and agreement (organization-level construct reliability and validity). CFAs for most constructs exhibited good model fit (CFI > 0.90, TLI > 0.90, SRMR < 0.08, RMSEA < 0.08), with almost all factor loadings exceeding 0.40. Scale reliabilities ranged from good (0.7 ≤ α < 0.9) to excellent (α ≥ 0.9). Scale correlations fell below 0.90, indicating discriminant validity. Inter-rater reliability and agreement were sufficiently high to justify measuring constructs at the clinic-level. Our findings provide psychometric evidence in support of the CFIR Inner Setting measures. Our findings also suggest the Inner Setting measures from individuals can be aggregated to represent the clinic-level. Measurement of the Inner Setting constructs can be useful in better understanding and predicting implementation in FQHCs and can be used to identify targets of strategies to accelerate and enhance implementation efforts in FQHCs.

11 November 2020 in Implementation Science Communications
Verified
Journal Article
Open access
PDF file
TWTimothy Walker
Timothy Walker
HBHeather Brandt
Heather Brandt
AWAbraham Wandersman
Abraham Wandersman
JSJonathan Scaccia
Jonathan Scaccia
ALAndrea Lamont
Andrea Lamont
MFMaria Fernández
Maria Fernández
Background: Organizational readiness is important for the implementation of evidence-based interventions. Currently, there is a critical need for a comprehensive, valid, reliable, and pragmatic measure of organizational readiness that can be used throughout the implementation process. This study aims to develop a readiness measure that can be used to support implementation in two critical public health settings: federally qualified health centers (FQHCs) and schools. The measure is informed by the Interactive Systems Framework for Dissemination and Implementation and R = MC2 heuristic (readiness = motivation × innovation-specific capacity × general capacity). The study aims are to adapt and further develop the readiness measure in FQHCs implementing evidence-based interventions for colorectal cancer screening, to test the validity and reliability of the developed readiness measure in FQHCs, and to adapt and assess the usability and validity of the readiness measure in schools implementing a nutrition-based program. Methods: For aim 1, we will conduct a series of qualitative interviews to adapt the readiness measure for use in FQHCs. We will then distribute the readiness measure to a developmental sample of 100 health center sites (up to 10 staff members per site). We will use a multilevel factor analysis approach to refine the readiness measure. For aim 2, we will distribute the measure to a different sample of 100 health center sites. We will use multilevel confirmatory factor analysis models to examine the structural validity. We will also conduct tests for scale reliability, test-retest reliability, and inter-rater reliability. For aim 3, we will use a qualitative approach to adapt the measure for use in schools and conduct reliability and validity tests similar to what is described in aim 2. Discussion: This study will rigorously develop a readiness measure that will be applicable across two settings: FQHCs and schools. Information gained from the readiness measure can inform planning and implementation efforts by identifying priority areas. These priority areas can inform the selection and tailoring of support strategies that can be used throughout the implementation process to further improve implementation efforts and, in turn, program effectiveness.

26 December 2016 in Journal of Occupational Rehabilitation
Verified
Journal Article
Closed access
PDF file
TWTimothy Walker
Timothy Walker
JTJessica M. Tullar
Jessica M. Tullar
PDPamela M. Diamond
Pamela M. Diamond
HKHarold W. Kohl
Harold W. Kohl
BABenjamin C. Amick
Benjamin C. Amick

2 October 2020 in BMC Public Health
Verified
Journal Article
Open access
PDF file
TWTimothy Walker
Timothy Walker
DCDerek Craig
Derek Craig
APAndjelka Pavlovic
Andjelka Pavlovic
STShelby Thiele
Shelby Thiele
HKHarold W. Kohl
Harold W. Kohl
Background: Schools play an important role in providing access to physical activity opportunities for children. There are common economic and gender disparities in physical activity and health-related fitness among children, which may inform a school’s programming needs. The purpose of this study is to gain a better understanding about gender, school-level socioeconomic status, and children’s cardiorespiratory fitness. Methods: This observational study used 2017–2018 school year data from schools in the Dallas Metropolitan area participating in the Healthy Zone School (HZS) program. Three data sources were integrated: 1) FitnessGram® data, 2) school-level data from the Texas Education Agency, and 3) HZS survey data. Being in the Healthy Fitness Zone (HFZ) for aerobic capacity was the dependent variable, and gender and the percentage of economically disadvantaged students (at the school-level) were key independent variables. Mixed-effects logistic regression models examined associations between dependent and independent variables. Final models were adjusted for age and type of aerobic test. Results: There were 67 schools and 15,052 students included in the analysis. When testing main effects, girls had lower odds for being in the HFZ for aerobic capacity than boys (OR = 0.54, CI = 0.47–0.62). Additionally, having a greater percentage of students who were economically disadvantaged was associated with lower odds for being in the HFZ for aerobic capacity (0.98, CI = 0.98–0.99). There was a significant interaction between gender and the percentage of economically disadvantaged students. Results indicated girls had even lower odds (than boys) for being in the HFZ in schools with 90% economically disadvantaged students (OR = 0.44, CI = 0.35–0.55) versus in schools with 15% economically disadvantage students (OR = 0.62, CI = 0.51–0.76). Conclusions: Results suggest girls in Healthy Zone Schools have lower odds to meet aerobic capacity fitness standards than boys. Additionally, boys and girls in schools serving a greater percentage of economically disadvantaged students have lower odds to meet aerobic capacity fitness standards. Last, girls have even lower odds of meeting HFZ standard when attending a school serving a greater percentage of economically disadvantaged students. Thus, schools need to provide more programs for girls targeting aerobic physical activity. This is especially important for schools serving a high percentage of low-income students.

29 March 2019 in BMC Health Services Research
Verified
Journal Article
Open access
PDF file
TWTimothy Walker
Timothy Walker
SRSerena A. Rodriguez
Serena A. Rodriguez
SVSally W. Vernon
Sally W. Vernon
LSLara S. Savas
Lara S. Savas
EFErica Frost
Erica Frost
MFMaria Fernández
Maria Fernández
Accurate and valid measures for implementation constructs are critical to advance research and guide implementation efforts. However, there is a continued need for valid and reliable measures for implementation research. The purpose of this study was to assess the psychometric properties of measures for the Inner Setting domain of the Consolidated Framework for Implementation Research (CFIR) in a network of pediatric clinics. This study used cross-sectional survey data collected from physicians, advanced practice providers, clinic managers, and clinical staff (n = 546) working in a pediatric clinic network (n = 51). Surveys included measures assessing Inner Setting constructs from CFIR (culture, learning climate, leadership engagement, and available resources). We used a series multilevel confirmatory factor analysis (CFA) models to assess factorial validity. We also examined measure correlations to test discriminant validity and intraclass correlation coefficients, ICC(1) and ICC(2), to assess inter-rater reliability. Factor loadings were high (≥0.60) for all but one of the measurement items. Most CFA models for respective constructs demonstrated adequate or good model fit (CFI > 0.90, TLI > 0.90, RMSEA< 0.08, and SRMR< 0.08). The measures also demonstrated good discriminant validity (correlations< 0.90) aside from some evidence of overlap between leadership engagement and learning climate at the clinic level (0.91). The ICC(1) values ranged from 0.05–0.16 while the ICC(2) values ranged from 0.34–0.67. The measures demonstrated good validity and adequate reliability with the exception of available resources, which had some evidence of lower than desired reliability and validity at the clinic level. Our findings extend previous work by providing additional psychometric evidence to support the use of these Inner Setting measures in pediatric clinics implementing human papillomavirus programs.

1 September 2017 in Preventive Medicine
Verified
Journal Article
Closed access
TWTimothy Walker
Timothy Walker
JTJessica M. Tullar
Jessica M. Tullar
PDPamela M. Diamond
Pamela M. Diamond
HKHarold W. Kohl
Harold W. Kohl
BABenjamin C. Amick
Benjamin C. Amick