Statistical Analysis with Missing Data

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Generalized Estimating Equations

Background
Many people with chronic disease have more than one chronic condition, which is referred to as multimorbidity. The term comorbidity is also used but this is now taken to mean that there is a defined index condition with other linked conditions, for example diabetes and cardiovascular disease. It is also used when there are combinations of defined conditions that commonly co-exist, for example diabetes and depression. While this is not a new phenomenon, there is greater recognition of its impact and the importance of improving outcomes for individuals affected. Research in the area to date has focused mainly on descriptive epidemiology and impact assessment. There has been limited exploration of the effectiveness of interventions to improve outcomes for people with multimorbidity.

Objectives
To determine the effectiveness of health-service or patient-oriented interventions designed to improve outcomes in people with multimorbidity in primary care and community settings. Multimorbidity was defined as two or more chronic conditions in the same individual.

Search methods
We searched MEDLINE, EMBASE, CINAHL and seven other databases to 28 September 2015. We also searched grey literature and consulted experts in the field for completed or ongoing studies.

Selection criteria
Two review authors independently screened and selected studies for inclusion. We considered randomised controlled trials (RCTs), non-randomised clinical trials (NRCTs), controlled before-after studies (CBAs), and interrupted time series analyses (ITS) evaluating interventions to improve outcomes for people with multimorbidity in primary care and community settings. Multimorbidity was defined as two or more chronic conditions in the same individual. This includes studies where participants can have combinations of any condition or have combinations of pre-specified common conditions (comorbidity), for example, hypertension and cardiovascular disease. The comparison was usual care as delivered in that setting.

Data collection and analysis
Two review authors independently extracted data from the included studies, evaluated study quality, and judged the certainty of the evidence using the GRADE approach. We conducted a meta-analysis of the results where possible and carried out a narrative synthesis for the remainder of the results. We present the results in a 'Summary of findings' table and tabular format to show effect sizes across all outcome types.

Main results
We identified 18 RCTs examining a range of complex interventions for people with multimorbidity. Nine studies focused on defined comorbid conditions with an emphasis on depression, diabetes and cardiovascular disease. The remaining studies focused on multimorbidity, generally in older people. In 12 studies, the predominant intervention element was a change to the organisation of care delivery, usually through case management or enhanced multidisciplinary team work. In six studies, the interventions were predominantly patient-oriented, for example, educational or self-management support-type interventions delivered directly to participants. Overall our confidence in the results regarding the effectiveness of interventions ranged from low to high certainty. There was little or no difference in clinical outcomes (based on moderate certainty evidence). Mental health outcomes improved (based on high certainty evidence) and there were modest reductions in mean depression scores for the comorbidity studies that targeted participants with depression (standardized mean difference (SMD) −2.23, 95% confidence interval (CI) −2.52 to −1.95). There was probably a small improvement in patient-reported outcomes (moderate certainty evidence) although two studies that specifically targeted functional difficulties in participants had positive effects on functional outcomes with one of these studies also reporting a reduction in mortality at four year follow-up (Int 6%, Con 13%, absolute difference 7%). The intervention may make little or no difference to health service use (low certainty evidence), may slightly improve medication adherence (low certainty evidence), probably slightly improves patient-related health behaviours (moderate certainty evidence), and probably improves provider behaviour in terms of prescribing behaviour and quality of care (moderate certainty evidence). Cost data were limited.

Authors' conclusions
This review identifies the emerging evidence to support policy for the management of people with multimorbidity and common comorbidities in primary care and community settings. There are remaining uncertainties about the effectiveness of interventions for people with multimorbidity in general due to the relatively small number of RCTs conducted in this area to date, with mixed findings overall. It is possible that the findings may change with the inclusion of large ongoing well-organised trials in future updates. The results suggest an improvement in health outcomes if interventions can be targeted at risk factors such as depression, or specific functional difficulties in people with multimorbidity.

Interventions for improving outcomes in patients with multimorbidity in primary care and community settings

STUDY OBJECTIVE
Frequent users of emergency departments (EDs) are a relatively small group of vulnerable patients accounting for a disproportionally high number of ED visits. Our objective is to perform a systematic review of the type and effectiveness of interventions to reduce the number of ED visits by frequent users.


METHODS
We searched MEDLINE, EMBASE, CINAHL, PsychINFO, the Cochrane Library, and ISI Web of Science for randomized controlled trials, nonrandomized controlled trials, interrupted time series, and controlled and noncontrolled before-and-after studies describing interventions targeting adult frequent users of EDs. Primary outcome of interest was the reduction in ED use. We also explored costs analyses and various clinical (alcohol and drug use, psychiatric symptoms, mortality) and social (homelessness, insurance status, social security support) outcomes.


RESULTS
We included 11 studies (3 randomized controlled trials, 2 controlled and 6 noncontrolled before-and-after studies). Heterogeneity in both study designs and definitions of frequent users precluded meta-analyses of the results. The most studied intervention was case management (n=7). Only 1 of 3 randomized controlled trials showed a significant reduction in ED use compared with usual care. Six of the 8 before-and-after studies reported a significant reduction in ED use, and 1 study showed a significant increase. ED cost reductions were demonstrated in 3 studies. Social outcomes such as reduction of homelessness were favorable in 3 of 3 studies, and clinical outcomes trended toward positive results in 2 of 3 studies.


CONCLUSION
Interventions targeting frequent users may reduce ED use. Case management, the most frequently described intervention, reduced ED costs and seemed to improve social and clinical outcomes. It appears to be beneficial to patients and justifiable for hospitals to implement case management for frequent users in the framework of a clear and consensual definition of frequent users and standardized outcome measures.

Effectiveness of interventions targeting frequent users of emergency departments: a systematic review

Objectives The aim of this study is to identify the types of community paramedicine programs and the training for each. Methods A systematic review of MEDLINE, Embase, grey literature, and bibliographies followed a search strategy using common community paramedicine terms. All studies published in English up to January 22, 2018, were captured. Screening and extraction were completed in duplicate by two independent reviewers. The Mixed Methods Appraisal Tool (MMAT) was used to assess studies' methodological quality (full methodology on PROSPERO: CRD42017051774). Results From 3,004 papers, there were 64 papers identified (58 unique community paramedicine programs). Of the papers with an appraisable study design (40.6%), the median MMAT score was 3 of 4 criteria met, suggesting moderate quality. Programs most often served frequent 911 callers (48.3%) and individuals at risk for emergency department admission, readmission, or hospitalization (41.4%); and 70.7% of programs were preventive home visits. Common services provided were home assessment (29.5%), medication management (39.7%), and referral and/or transport to community services (37.9%); and 77.6% of programs involved interprofessional collaboration. Community paramedicine training was described by 57% of programs and expanded upon traditional paramedicine training and emphasized technical skills. Study heterogeneity prevented meta-analysis. Conclusion Community paramedicine programs and training were diverse and allowed community paramedics to address a spectrum of population health and social needs. Training was poorly described. Enabling more programs to assess and report on program and training outcomes would support community paramedicine growth and the development of formalized training or education frameworks.

/pdf/community-paramedicine-a-systematic-review-of-program-zha41vt51f.pdf

Community paramedicine: A systematic review of program descriptions and training

Disseminating the Canadian Diabetes Association 2013 Clinical Practice Guidelines: Guidelines.diabetes.ca in Action

Background: Community paramedicine (CP) expands the paramedic role to emergency call prevention, yet little research has examined paramedics’ perspectives of CP. Aims: This study sought to explore paramedics’ views regarding the CP role and training. Methods: A cross-sectional, web-based survey of Ontario paramedics measured perceptions, support and interest in CP. Descriptive and regression analyses were conducted. Findings: Of the 452 participants, 57.5% were male, 43.6% primary care paramedics and 33.0% had a history of being on modified duty. Paramedics perceived CP to include treat-and-release (85.4%), community resource referrals (79.0%), expanded skills (77.9%), community education (75.9%) and follow-up (73.7%). Most were supportive (82.8%) and interested in participating (72.3%). Interest in training was lower in respondents with 20 or more years of service and higher in those with a history of modified duty (p<0.05). Conclusion: Paramedics are aware the CP role has multiple functions and are supportive and interested in CP. This study has implications for services as CP expands globally.

/pdf/paramedics-perspectives-of-the-community-paramedic-role-in-g13m85c7.pdf

Brent McLeod

Papers

Disseminating the Canadian Diabetes Association 2013 Clinical Practice Guidelines: Guidelines.diabetes.ca in Action

Paramedics’ perspectives of the community paramedic role in Ontario, Canada