Health and Care Data: Approaches to data linkage for evidence-informed policy.

An indispensable prerequisite for answering research questions in health services research is the availability and accessibility of comprehensive, high-quality data. It can be assumed that health services research in the coming years will be increasingly based on data linkage, i.e., the linking, or connecting, of several data sources based on suitable common key variables. A range of approaches to data collection, storage, linkage and availability exists across countries, particularly for secondary research purposes (i.e., the use of data initially collected for other purposes), such as health systems research. The main goal of this review is to develop an overview of, and gain insights into, current approaches to linking data sources in the context of health services research, with the view to inform policy, based on existing practices in high-income countries in Europe and beyond. In doing so, another objective is to provide lessons for countries looking for possible or alternative approaches to data linkage. Thirteen country case studies of data linkage approaches were selected and analysed. Rather than being comprehensive, this review aimed to identify varied and potentially useful case studies to showcase different approaches to data linkage worldwide. A conceptual framework was developed to guide the selection and description of case studies. Information was first identified and collected from publicly available sources and a profile was then created for each country and each case study; these profiles were forwarded to appropriate country experts for validation and completion. The report presents an overview of the included countries and their case studies (Chapter 2), with key data per country and case study in the appendices. This is followed by a closer look at the possibilities of using routine data (Chapter 3); the different approaches to linkage (Chapter 4); the different access routes for researchers (Chapter 5); the use of data for research from electronic patient or health records (Chapter 6); foundational considerations related to data safety, privacy and governance (Chapter 7); recent developments in cross-border data sharing and the European Health Data Space (Chapter 8); and considerations of changes and responses catalysed by the COVID-19 pandemic as related to the generation and secondary use of data (Chapter 9). The review ends with overall conclusions on the necessary characteristics of data to inform research relevant for policy and highlights some insights to inspire possible future solutions - less or more disruptive - for countries looking to expand their use of data (Chapter 10). It emphasises that investing in data linkage for secondary use will not only contribute to the strengthening of national health systems, but also promote international cooperation and contribute to the international visibility of scientific excellence.

Mediational pathways of tobacco use among adult daily smokers with psychiatric symptoms in the Population Assessment of Tobacco and Health (PATH) survey.

INTRODUCTION: Individuals with psychiatric conditions suffer disproportionately from tobacco-related morbidity and mortality, but the factors driving this relationship remain unclear. We used data from the Population Assessment of Tobacco and Health (PATH) to investigate whether associations between internalizing psychiatric symptoms and change in smoking heaviness (as measured by cigarettes per day (CPD) were mediated by self-reported respiratory symptoms, smoking risk perceptions, and cigarette dependence. METHODS: This study used data from PATH Waves 1 through 4 (2013-2017, n = 4,152). Psychiatric symptoms were indexed with the internalizing sub-scale of the Global Appraisal of Individual Needs-Short Screener (GAIN-SS) among daily smokers. We fit auto-regressive structural equation models (SEM) to data from Wave 1-3 and 2-4 to determine the direct and indirect associations between internalizing symptom scores and CPD through each mediator. RESULTS: The association between internalizing symptoms and CPD was mediated by cigarette dependence (indirect: B = 0.004, SE = 0.041, p = 0.023) and respiratory symptom severity (indirect: B = 0.018, SE = 0.097, p < 0.001). Internalizing symptoms predicted higher harm perceptions (B = 0.056, SE = 0.035, p < 0.001) but the indirect relationship with CPD was non-significant. Findings from Waves 2-4 replicated these results. CONCLUSION: Our results indicate that cigarette dependence and respiratory symptom severity partially mediate the relationship between internalizing symptoms and CPD but risk perceptions were not significant predictors in our models. This suggests that efforts to reduce smoking among people with internalizing disorders should focus on decreasing nicotine dependence and increasing awareness of respiratory symptoms to encourage a quit attempt or switch to a less harmful source of nicotine.

Effects of Very Low Nicotine Content Cigarette use on Cigarette Reinforcement among Smokers with Serious Mental Illness.

BACKGROUND: Among people without psychiatric disorders who smoke, very low nicotine content (VLNC) cigarette use reduces cigarette reinforcement. Whether this is true of people with serious mental illness (SMI) who smoke is unknown. Using a hypothetical purchase task, we compared the effects of 6-week use of VLNC versus normal nicotine content (NNC) cigarettes on study cigarette and usual brand (UB) cigarette reinforcement among people with SMI who smoke. METHODS: After a baseline period of UB cigarette use, participants with SMI (n = 58) were randomized to use NNC cigarettes (15.8 mg nicotine/g tobacco) or VLNC cigarettes (0.4 mg/g) for 6 weeks. At Week 6, they completed the CPT for both their assigned study cigarette and UB. The groups were compared on demand intensity (number of cigarettes purchased at no cost) and elasticity (rate of decline in demand as price increases) using extra sum-of-squares F-tests. The effects of treatment on demand indices while controlling for covariates were assessed using hierarchical regression. RESULTS: At Week 6, intensity of demand for study cigarettes was lower and elasticity was higher for the VLNC group relative to the NNC group (p < 0.0001). Furthermore, intensity of demand for UB cigarettes was lower for participants in the VLNC group relative to participants in the NNC group (p < 0.01). When controlling for baseline cigarettes per day, intensity remained significantly different for study cigarettes and usual brand cigarettes at Week 6. CONCLUSION: A nicotine reduction policy may reduce cigarette reinforcement in this vulnerable population.

A longitudinal assessment of nicotine dependence, mental health, and attempts to quit Smoking: Evidence from waves 1-4 of the Population Assessment of Tobacco and Health (PATH) study.

BACKGROUND: Adult smokers with symptoms of any mental illness (AMI) are highly dependent on nicotine and may face additional difficulty quitting smoking. While there is evidence that adult smokers with AMI have high dependence, there is insufficient evidence regarding the unique role that AMI may play in moderating the relationship between dependence and cessation outcomes over time. METHODS: 7290 current established adult smokers at Wave 1 (2013-2014) of the PATH Study also participated in data collection in Waves 2-4 (2014-2018). Linear probability models with individual-level random effects were fit to the data, modeling associations between AMI, nicotine dependence, and the 1) likelihood of achieving cessation during the study period, 2) making a cessation attempt within the previous 12 months, and 3) log of past 30-day total consumption of cigarettes. RESULTS: Adults who experienced both AMI symptoms and high dependence were 4.7 percentage points (PP) less likely to achieve cessation at any point during the study period (p < 0.01) and smoked more cigarettes per month (ß = 0.214, p < 0.05) than adults with AMI who were not highly dependent, despite being as likely to attempt to quit. Adults with AMI who were not highly dependent were 4.6 PP more likely to report a quit attempt and 1.6 PP more likely to achieve cessation than those with neither AMI nor high dependence. CONCLUSIONS: Adults with AMI are particularly affected by the burden of tobacco use, in part because of the likely interaction between nicotine dependence and AMI. Tobacco control efforts that focus on this interplay may provide an opportunity to better target interventions for this vulnerable population.