Evidence map›Paper›PMID 26578402›Full record

ArticlePharmacoEconomics2016

Using Classification and Regression Trees (CART) to Identify Prescribing Thresholds for Cardiovascular Disease.

Chris Schilling, Duncan Mortimer, Kim Dalziel, Emma Heeley, John Chalmers, Philip Clarke

Open access · greenAbstract read
PubMed Publisher
In one paragraph

Article in PharmacoEconomics, 2016. The graph could read no effect estimate from its abstract, so it casts no vote on the map. Cited by 11 papers.

0numbers the graph read from it
0cells of the map it votes in
11citing papers in PubMed
2.1field-weighted citation impact, top 13% of its field
1 · What the graph read from it

What it found

Each row is one number read from the abstract, on the scale the paper reported it, with its interval. Left of the dashed line favours the treatment, right favours the comparator. Under each row is the sentence it came from. New to these charts? A ten-minute tutorial.

The abstract states no effect estimate the extractor could read, or names no intervention and outcome on the map, so this paper lights no cell and moves no belief. It is still indexed, cited and linked below.

2 · The registry

The trial behind it

Trials whose registry record cites this paper, or whose number appears in the abstract. A trial that started after this paper was published is citing it as background, not reporting it.

Neither the registry nor the abstract names a trial number. If this is a trial report, that itself is worth knowing.

3 · Its place in the literature

Who cites it

11 citing papers in PubMed, 27 citations in OpenAlex.

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4 · The record

Corrections and comments

PubMed lists nothing against this paper. Absence here is not a guarantee, only a check that was made.

5 · Who and what money

Authors and funding

6 authors at 5 institutions in 1 country.

Chris SchillingCentre for Health Policy, School of Population and Global Health, University of Melbourne, Melbourne, VIC, 3051, Australia. chris.schilling@unimelb.edu.au.
Duncan MortimerCentre for Health Economics, Monash Business School, Monash University, Melbourne, VIC, 3800, Australia.
Kim DalzielCentre for Health Policy, School of Population and Global Health, University of Melbourne, Melbourne, VIC, 3051, Australia.
Emma HeeleyThe George Institute for Global Health, The University of Sydney and the Royal Prince Alfred Hospital, Sydney, NSW, 2050, Australia.
John ChalmersThe George Institute for Global Health, The University of Sydney and the Royal Prince Alfred Hospital, Sydney, NSW, 2050, Australia.
Philip ClarkeCentre for Health Policy, School of Population and Global Health, University of Melbourne, Melbourne, VIC, 3051, Australia.
University of Melbourne · AUMelbourne Health · AUMonash University · AURoyal Prince Alfred Hospital · AUThe George Institute for Global Health · AU

Funding

No grant is acknowledged in the PubMed record.

6 · The paper itself

Abstract

BACKGROUND AND

objectiveMany guidelines for clinical decisions are hierarchical and nonlinear. Evaluating if these guidelines are used in practice requires methods that can identify such structures and thresholds. Classification and regression trees (CART) were used to analyse prescribing patterns of Australian general practitioners (GPs) for the primary prevention of cardiovascular disease (CVD). Our aim was to identify if GPs use absolute risk (AR) guidelines in favour of individual risk factors to inform their prescribing decisions of lipid-lowering medications.

methodsWe employed administrative prescribing information that is linked to patient-level data from a clinical assessment and patient survey (the AusHeart Study), and assessed prescribing of lipid-lowering medications over a 12-month period for patients (n = 1903) who were not using such medications prior to recruitment. CART models were developed to explain prescribing practice. Out-of-sample performance was evaluated using receiver operating characteristic (ROC) curves, and optimised via pruning.

resultsWe found that individual risk factors (low-density lipoprotein, diabetes, triglycerides and a history of CVD), GP-estimated rather than Framingham AR, and sociodemographic factors (household income, education) were the predominant drivers of GP prescribing. However, sociodemographic factors and some individual risk factors (triglycerides and CVD history) only become relevant for patients with a particular profile of other risk factors. The ROC area under the curve was 0.63 (95% confidence interval [CI] 0.60-0.64).

conclusionsThere is little evidence that AR guidelines recommended by the National Heart Foundation and National Vascular Disease Prevention Alliance, or conditional individual risk eligibility guidelines from the Pharmaceutical Benefits Scheme, are adopted in prescribing practice. The hierarchy of conditional relationships between risk factors and socioeconomic factors identified by CART provides new insights into prescribing decisions. Overall, CART is a useful addition to the analyst's toolkit when investigating healthcare decisions.

Indexed as

Practice Guidelines as TopicAgedAustraliaCardiovascular DiseasesClinical Decision-MakingDecision TreesFemaleGeneral PractitionersHumansHypolipidemic AgentsMaleMiddle AgedPractice Patterns, Physicians'Primary PreventionRisk FactorsSocioeconomic FactorsHypolipidemic AgentsTriglycerides

Identifiers

PMID26578402
OpenAlexW2220118211

What OpenQuestion holds

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Read underepoch 390

Registered trials

None linked

Read under generation 80e0d062 · epoch 390. Bibliography from PubMed, PubMed Central and OpenAlex; grants from NIH RePORTER; trial links from ClinicalTrials.gov; estimates, votes and beliefs from the OpenQuestion graph.