Evidence map›Paper›PMID 24614626›Full record

ArticlePloS one2014

Sequential cohort design applying propensity score matching to analyze the comparative effectiveness of atorvastatin and simvastatin in preventing cardiovascular events.

Arja Helin-Salmivaara, Piia Lavikainen, Emma Aarnio, Risto Huupponen, Maarit Jaana Korhonen

Erratum issuedOpen access · goldFull text read
PubMed Full text at PMC Publisher
In one paragraph

Article in PloS one, 2014. The graph could read no effect estimate from its abstract, so it casts no vote on the map. An erratum has been issued. Cited by 5 papers.

0numbers the graph read from it
0cells of the map it votes in
5citing papers in PubMed
4.6field-weighted citation impact, top 5% 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

5 citing papers in PubMed, 7 citations in OpenAlex.

  1. Article
  2. Observational
  3. Article
  4. Article
  5. Article
4 · The record

Corrections and comments

  • Erratum issued
5 · Who and what money

Authors and funding

5 authors at 3 institutions in 1 country.

Arja Helin-SalmivaaraDepartment of Pharmacology, Drug Development and Therapeutics, University of Turku, Turku, Finland; Unit of Primary Health Care, Hospital District of Helsinki and Uusimaa, Helsinki, Finland.
Piia LavikainenDepartment of Pharmacology, Drug Development and Therapeutics, University of Turku, Turku, Finland.
Emma AarnioDepartment of Clinical Pharmacology, Tykslab, Turku University Hospital, Turku, Finland; School of Pharmacy, University of Eastern Finland, Kuopio, Finland.
Risto HuupponenDepartment of Pharmacology, Drug Development and Therapeutics, University of Turku, Turku, Finland; Department of Clinical Pharmacology, Tykslab, Turku University Hospital, Turku, Finland.
Maarit Jaana KorhonenDepartment of Pharmacology, Drug Development and Therapeutics, University of Turku, Turku, Finland; Department of Public Health, University of Turku, Turku, Finland.
University of Turku · FIHospital District of Helsinki and Uusimaa · FIUniversity of Eastern Finland · FI

Funding

No grant is acknowledged in the PubMed record.

6 · The paper itself

Abstract

backgroundSequential cohort design (SCD) applying matching for propensity scores (PS) in accrual periods has been proposed to mitigate bias caused by channeling when calendar time is a proxy for strong confounders. We studied the channeling of patients according to atorvastatin and simvastatin initiation in Finland, starting from the market introduction of atorvastatin in 1998, and explored the SCD PS approach to analyzing the comparative effectiveness of atorvastatin versus simvastatin in the prevention of cardiovascular events (CVE).

methodsInitiators of atorvastatin or simvastatin use in the 45-75-year age range in 1998-2006 were characterized by their propensity of receiving atorvastatin over simvastatin, as estimated for 17 six-month periods. Atorvastatin (10 mg) and simvastatin (20 mg) initiators were matched 1∶1 on the PS, as estimated for the whole cohort and within each period. Cox regression models were fitted conventionally, and also for the PS matched cohort and the periodically PS matched cohort, to estimate the hazard ratios (HR) for CVEs.

findingsAtorvastatin (10 mg) was associated with a 11%-12% lower incidence of CVE in comparison with simvastatin (20 mg). The HR estimates were the same for a conventional Cox model (0.88, 95% confidence interval 0.85-0.91), for the analysis in which the PS was used to match across all periods and the Cox model was adjusted for strong confounders (0.89, 0.85-0.92), and for the analysis in which PS matching was applied within sequential periods (0.88, 0.84-0.92). The HR from a traditional PS matched analysis was 0.80 (0.77-0.83).

conclusionsThe SCD PS approach produced effect estimates similar to those obtained in matching for PS within the whole cohort and adjusting the outcome model for strong confounders, but at the cost of efficiency. A traditional PS matched analysis without further adjustment in the outcome model produced estimates further away from unity.

Indexed as

Comparative Effectiveness ResearchPropensity ScoreAgedAtorvastatinCardiovascular DiseasesCohort StudiesFinlandHumansHydroxymethylglutaryl-CoA Reductase InhibitorsMiddle AgedSimvastatinAtorvastatinHydroxymethylglutaryl-CoA Reductase InhibitorsSimvastatin

Identifiers

PMID24614626
PMCPMC3948677
OpenAlexW2049394404

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Registered trials

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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.