The high prevalence of back and neck pain results in enormous social, psychological, and economic burden. Most seeking help for back or neck pain consult general practitioners or chiropractors. Chiropractic is a regulated health profession (serving approximately 10 – 15% of the population) that has contributed to the health and well-being of North Americans for over a century. Despite available evidence for optimal management of back and neck pain, poor adherences to guidelines and wide variations in services have been noted. For instance, overuse and misuse of imaging services have been reported in the chiropractic literature. Inappropriate use of spine imaging has a number of potential adverse outcomes, including inefficient and potentially inappropriate invasive diagnosis and subsequent treatment, and unnecessary patient exposure to ionizing radiation. Although evidence-based diagnostic imaging guidelines for spinal disorders are available, chiropractors are divided on whether these guidelines apply to them. While guidelines can encourage practitioners to conform to best practices and lead to improvements in care, reviews have demonstrated that dissemination of guidelines alone is rarely sufficient to optimise care. Evidence regarding effective methods to promote the uptake of guidelines is still lacking. There is growing acceptance that problem analysis and development of interventions to change practice should be guided by relevant theories and tailored to the target audience. To date, very little knowledge translation research has addressed research-practice gaps in chiropractic. This thesis reports rigorous methods to: (1) assess practice and providers’ characteristics, (2) determine baseline rates and variations in spine x-ray ordering, (3) evaluate the impact of disseminating guidelines to optimise spine x-ray ordering, and (4) assess determinants of spine x-ray ordering and potential targets for change prior to the design of a tailored intervention. A mixed method using two disciplinary perspectives (epidemiology and psychology) was undertaken. A cross-sectional analysis of administrative claims data was carried out on a sample of chiropractors enlisted in a large American provider network. Despite available clinical practice guidelines, wide geographical variations in x-ray use persist. Higher x-ray ordering rates were associated with practice location (Midwest and South US census regions), setting (urban, suburban), chiropractic school attended, male provider, employment, and years in practice. The impact of web-based guideline dissemination was evaluated over a five year period using interrupted time series and demonstrated a stepwise relative reduction of 5.3% in the use of x-rays. Passive guidelines dissemination appeared to be a simple, cost effective strategy in this setting to improve but not optimise x-ray ordering rates. Focus groups using the theoretical domains framework were conducted among Canadian and US chiropractors to explore their beliefs about managing back pain without x-rays. Findings were used to develop a theory-based survey to identify theoretical constructs predicting spine x-ray ordering practice. Psychological theories and theoretical constructs explained a significant portion of the variance in both behavioural simulation and intention. Results from this thesis provide an empirically-supported, theoretical basis to design quality improvement strategies to increase guidelines adherence and promote behaviour change in chiropractic. Other researchers interested in improving uptake of evidenced-based information could use this method in their own setting to investigate determinants of behaviour among other professional groups. Future research may use knowledge gained to inform the development and evaluation of a theory-based tailored intervention to improve guideline adherence and reduce the use of spine x-rays among targeted providers.

The high prevalence of back and neck pain results in enormous social, psychological, and economic burden. Most seeking help for back or neck pain consult general practitioners or chiropractors. Chiropractic is a regulated health profession (serving approximately 10 – 15% of the population) that has contributed to the health and well-being of North Americans for over a century. Despite available evidence for optimal management of back and neck pain, poor adherences to guidelines and wide variations in services have been noted. For instance, overuse and misuse of imaging services have been reported in the chiropractic literature. Inappropriate use of spine imaging has a number of potential adverse outcomes, including inefficient and potentially inappropriate invasive diagnosis and subsequent treatment, and unnecessary patient exposure to ionizing radiation. Although evidence-based diagnostic imaging guidelines for spinal disorders are available, chiropractors are divided on whether these guidelines apply to them. While guidelines can encourage practitioners to conform to best practices and lead to improvements in care, reviews have demonstrated that dissemination of guidelines alone is rarely sufficient to optimise care. Evidence regarding effective methods to promote the uptake of guidelines is still lacking. There is growing acceptance that problem analysis and development of interventions to change practice should be guided by relevant theories and tailored to the target audience. To date, very little knowledge translation research has addressed research-practice gaps in chiropractic. This thesis reports rigorous methods to: (1) assess practice and providers’ characteristics, (2) determine baseline rates and variations in spine x-ray ordering, (3) evaluate the impact of disseminating guidelines to optimise spine x-ray ordering, and (4) assess determinants of spine x-ray ordering and potential targets for change prior to the design of a tailored intervention. A mixed method using two disciplinary perspectives (epidemiology and psychology) was undertaken. A cross-sectional analysis of administrative claims data was carried out on a sample of chiropractors enlisted in a large American provider network. Despite available clinical practice guidelines, wide geographical variations in x-ray use persist. Higher x-ray ordering rates were associated with practice location (Midwest and South US census regions), setting (urban, suburban), chiropractic school attended, male provider, employment, and years in practice. The impact of web-based guideline dissemination was evaluated over a five year period using interrupted time series and demonstrated a stepwise relative reduction of 5.3% in the use of x-rays. Passive guidelines dissemination appeared to be a simple, cost effective strategy in this setting to improve but not optimise x-ray ordering rates. Focus groups using the theoretical domains framework were conducted among Canadian and US chiropractors to explore their beliefs about managing back pain without x-rays. Findings were used to develop a theory-based survey to identify theoretical constructs predicting spine x-ray ordering practice. Psychological theories and theoretical constructs explained a significant portion of the variance in both behavioural simulation and intention. Results from this thesis provide an empirically-supported, theoretical basis to design quality improvement strategies to increase guidelines adherence and promote behaviour change in chiropractic. Other researchers interested in improving uptake of evidenced-based information could use this method in their own setting to investigate determinants of behaviour among other professional groups. Future research may use knowledge gained to inform the development and evaluation of a theory-based tailored intervention to improve guideline adherence and reduce the use of spine x-rays among targeted providers.

The high prevalence of back and neck pain results in enormous social, psychological, and economic burden. Most seeking help for back or neck pain consult general practitioners or chiropractors. Chiropractic is a regulated health profession (serving approximately 10 – 15% of the population) that has contributed to the health and well-being of North Americans for over a century. Despite available evidence for optimal management of back and neck pain, poor adherences to guidelines and wide variations in services have been noted. For instance, overuse and misuse of imaging services have been reported in the chiropractic literature. Inappropriate use of spine imaging has a number of potential adverse outcomes, including inefficient and potentially inappropriate invasive diagnosis and subsequent treatment, and unnecessary patient exposure to ionizing radiation. Although evidence-based diagnostic imaging guidelines for spinal disorders are available, chiropractors are divided on whether these guidelines apply to them. While guidelines can encourage practitioners to conform to best practices and lead to improvements in care, reviews have demonstrated that dissemination of guidelines alone is rarely sufficient to optimise care. Evidence regarding effective methods to promote the uptake of guidelines is still lacking. There is growing acceptance that problem analysis and development of interventions to change practice should be guided by relevant theories and tailored to the target audience. To date, very little knowledge translation research has addressed research-practice gaps in chiropractic. This thesis reports rigorous methods to: (1) assess practice and providers’ characteristics, (2) determine baseline rates and variations in spine x-ray ordering, (3) evaluate the impact of disseminating guidelines to optimise spine x-ray ordering, and (4) assess determinants of spine x-ray ordering and potential targets for change prior to the design of a tailored intervention. A mixed method using two disciplinary perspectives (epidemiology and psychology) was undertaken. A cross-sectional analysis of administrative claims data was carried out on a sample of chiropractors enlisted in a large American provider network. Despite available clinical practice guidelines, wide geographical variations in x-ray use persist. Higher x-ray ordering rates were associated with practice location (Midwest and South US census regions), setting (urban, suburban), chiropractic school attended, male provider, employment, and years in practice. The impact of web-based guideline dissemination was evaluated over a five year period using interrupted time series and demonstrated a stepwise relative reduction of 5.3% in the use of x-rays. Passive guidelines dissemination appeared to be a simple, cost effective strategy in this setting to improve but not optimise x-ray ordering rates. Focus groups using the theoretical domains framework were conducted among Canadian and US chiropractors to explore their beliefs about managing back pain without x-rays. Findings were used to develop a theory-based survey to identify theoretical constructs predicting spine x-ray ordering practice. Psychological theories and theoretical constructs explained a significant portion of the variance in both behavioural simulation and intention. Results from this thesis provide an empirically-supported, theoretical basis to design quality improvement strategies to increase guidelines adherence and promote behaviour change in chiropractic. Other researchers interested in improving uptake of evidenced-based information could use this method in their own setting to investigate determinants of behaviour among other professional groups. Future research may use knowledge gained to inform the development and evaluation of a theory-based tailored intervention to improve guideline adherence and reduce the use of spine x-rays among targeted providers.

The purpose of this exploratory study was to examine the extent to which pretreatment characteristics influence therapist treatment adherence by using data sampled from a randomized effectiveness trial and an efficacy study. Research suggests that youth-, family-, and therapist-level pretreatment characteristics influence therapist behavior; however, this area is underdeveloped as most studies have focused on externalizing problem areas, family-based approaches, and the use of parent or therapist report to assess for therapist adherence. To date, no research has examined this question with anxiety as the target problem, individual-focused CBT, and with observational therapist adherence data. An observational coding measure, Cognitive-Behavioral Therapy Adherence Scale for Youth Anxiety, was used to assess therapist adherence to CBT for youth anxiety. Hierarchical linear model analyses were conducted to estimate changes in therapist adherence over time, based on youth-, family-, and therapist-level pretreatment characteristic predictors. Results suggest that youth ethnicity/race, therapist openness to evidence-based practices, therapist theoretical orientation, and therapist age influence the process of therapy: in this case, therapist adherence. The current study provides essential evidence about potentially important predictors of therapist adherence for CBT youth anxiety and points to important clinical and treatment adoption implications.

Essay #1 - Parental Social Influence in Childhood Obesity Interventions: a Systematic Review The objective of this study is to understand the pathways through which social influence at the family level moderates childhood obesity interventions. We conducted a systematic review of obesity interventions in which parents' behaviors are targeted to change children's obesity outcomes, due to the potential social and environmental influence of parents on the nutrition and physical activity behaviors of children. Results for existing mechanisms that moderate parents' influence on children's behavior are discussed and a causal pathway diagram is developed to map out social influence mechanisms that affect childhood obesity. We provide health professionals and researchers with recommendations to leverage family-based social influence mechanisms for increasing the efficacy of the obesity intervention programs. Essay #2 - Dynamics of Obesity Interventions inside Organizations: a Case Study of Food Carry-Outs in Baltimore A large number of obesity prevention interventions, from upstream (policy and environmental) to downstream (individual level), have been put forward to curb the obesity trend; however, not all those interventions have been successful. Overall effectiveness of obesity prevention interventions relies not only on the average efficacy of a generic intervention, but also on the successful Reach, Effectiveness, Adoption, Implementation, and Maintenance (RE-AIM) of that intervention. In this study, we aim to understand how effectiveness of organizational level obesity prevention interventions depends on dynamics of AIM. We focus on an obesity prevention intervention, implemented in food carry-outs in low-income urban areas of Baltimore city, which aims to improve dietary behavior for adults through better food access to healthier foods and point-of-purchase prompts. Building on data from interviews and the literature we develop a dynamic model of the key processes of AIM. We first develop a contextualized map of causal relationships integral to the dynamics of AIM, and then quantify those mechanisms using a system dynamics simulation model. With simulation analysis, we show how as a result of several reinforcing loops that span stakeholder motivation, communications, and implementation quality and costs, small changes in the process of AIM can make a big difference in impact. We present how the dynamics surrounding communication, motivation, and depreciation of interventions can create tipping dynamics in AIM. Specifically, small changes in allocation of resources to an intervention could have a disproportionate long-term impact if those additional resources can turn stakeholders into allies of the intervention, reducing the depreciation rates and enhancing sustainability. We provide researchers with a set of recommendations to increase the sustainability of the interventions. Essay #3 - Dynamics of Implementation and Maintenance of Organizational Health Interventions: Case Studies of Obesity Interventions In this study, we present case studies to explore the dynamics of implementation and maintenance of obesity interventions. We analyze how specific obesity prevention interventions are built and eroded, how the building and erosion mechanisms are interconnected, and why we can see significantly different erosion rates across otherwise similar organizations. We use multiple comparative case studies to provide empirical information on the mechanisms of interest, and use qualitative systems modeling to integrate our evolving understanding into an internally consistent and transparent theory of the phenomenon. Our preliminary results identify reinforcing feedback mechanisms, including design of organizational processes, motivation of stakeholders, and communication among stakeholders, which influence implementation and maintenance of intervention components. Over time, these feedback mechanisms may drive a wedge between otherwise similar organizations, leading to distinct configurations of implementation and maintenance processes. / Ph. D.