Using propensity scores to estimate effects of treatment initiation decisions: State of the science

BackgroundClozapine is uniquely effective in treatment-resistant psychosis but remains underutilised, partly owing to psychotic symptoms leading to non-adherence to oral medication. An intramuscular formulation is available in the UK but outcomes remain unexplored.AimsThis was a retrospective clinical effectiveness study of intramuscular clozapine prescription for treatment initiation and maintenance in treatment-resistant psychosis over a 3-year period.MethodSuccessful initiation of oral clozapine after intramuscular prescription was the primary outcome. Secondary outcomes included all-cause clozapine discontinuation 2 years following initiation, and 1 year after discharge. Discontinuation rates were compared with a cohort prescribed only oral clozapine. Propensity scores were used to address confounding by indication.ResultsAmong 39 patients prescribed intramuscular clozapine, 19 received at least one injection, whereas 20 accepted oral clozapine when given an enforced choice between the two. Thirty-six (92%) patients successfully initiated oral clozapine after intramuscular prescription; three never transitioned to oral. Eight discontinued oral clozapine during the 2-year follow-up, compared with 83 out of 162 in the comparator group (discontinuation rates of 24% and 50%, respectively). Discontinuation rates at 1-year post-discharge were 21%, compared with 44% in the comparison group. Intramuscular clozapine prescription was associated with a non-significantly lower hazard of discontinuation 2 years after initiation (hazard ratio 0.39, 95% CI 0.14–1.06) and 1 year after discharge (hazard ratio 0.37, 95% CI 0.11–1.24). The only reported adverse event specific to the intramuscular formulation was injection site pain and swelling.ConclusionsIntramuscular clozapine prescription allowed transition to oral maintenance in an initially non-adherent cohort. Discontinuation rates were similar to patients only prescribed oral clozapine and comparable to existing literature.

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Laboratory Reporting of Tuberculosis Test Results and Patient Treatment Initiation in California

Yearbook of Pathology and Laboratory Medicine ◽

10.1016/s1077-9108(08)70188-9 ◽

2006 ◽

Vol 2006 ◽

pp. 259

Author(s):

M.G. Bissell

Keyword(s):

Treatment Initiation ◽

Patient Treatment ◽

Test Results

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Klinische und psychosoziale Charakteristika bei Suchtpatienten mit und ohne PTBS

SUCHT - Zeitschrift für Wissenschaft und Praxis / Journal of Addiction Research and Practice ◽

10.1024/0939-5911/a000512 ◽

2017 ◽

Vol 63 (6) ◽

pp. 315-324

Author(s):

Anja Hildebrand ◽

Heinz C. Vollmer ◽

Julia Domma-Reichart

Keyword(s):

Propensity Scores

Zusammenfassung. Hintergrund: In Deutschland liegen nur vereinzelte Studien zur PTBS-Prävalenzquote bei Suchtpatienten und zu deren psychischen Befund vor. Fragestellung: Wie hoch ist die relative Häufigkeit einer PTBS bei Patienten mit substanzbezogenen Störungen und wie unterscheiden sich die Patienten mit und ohne PTBS hinsichtlich klinischer und psychosozialer Charakteristika? Methode: Mittels Chi-Quadrat- und t-Tests wurden 376 mittels Propensity Scores gematchte Patienten aus einer Stichprobe von 4105 konsekutiv aufgenommenen Abhängigen in diagnostischen und psychischen Merkmalen retrospektiv miteinander verglichen. Ergebnisse: Die relative Häufigkeit von PTBS lag bei den Patienten mit einer alkoholbezogenen Störung bei 3,8 %, bei den restlichen Suchtpatienten mit Störungen durch andere psychotrope Substanzen bei 10,5 %. Bei den PTBS Patienten lag häufiger eine Persönlichkeitsstörung vor. Außerdem waren die PTBS Patienten stärker psychisch belastet, in ihrem Interaktionsstil abweisender, introvertierter, und nachgiebiger sowie im Bindungsstil vermeidender. Schlussfolgerungen: Die Unterschiede verdeutlichen die Notwendigkeit von auf den Interaktions- und Bindungsstil individuell angepassten Interventionen im Rahmen der Standardbehandlungen für Suchtpatienten mit PTBS.

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Validating Four Standard Scales in Spiritually Practicing and Nonpracticing Samples Using Propensity Score Matching

European Journal of Psychological Assessment ◽

10.1027/1015-5759.24.3.165 ◽

2008 ◽

Vol 24 (3) ◽

pp. 165-173 ◽

Cited By ~ 8

Author(s):

Niko Kohls ◽

Harald Walach

Keyword(s):

Propensity Score ◽

Propensity Score Matching ◽

Repeated Measures ◽

Propensity Scores ◽

Total Sample ◽

Experimental Manipulation ◽

Brief Symptom Inventory ◽

Time Interaction ◽

Social Support Scale ◽

Lower Test

Validation studies of standard scales in the particular sample that one is studying are essential for accurate conclusions. We investigated the differences in answering patterns of the Brief-Symptom-Inventory (BSI), Transpersonal Trust Scale (TPV), Sense of Coherence Questionnaire (SOC), and a Social Support Scale (F-SoZu) for a matched sample of spiritually practicing (SP) and nonpracticing (NSP) individuals at two measurement points (t1, t2). Applying a sample matching procedure based on propensity scores, we selected two sociodemographically balanced subsamples of N = 120 out of a total sample of N = 431. Employing repeated measures ANOVAs, we found an intersample difference in means only for TPV and an intrasample difference for F-SoZu. Additionally, a group × time interaction effect was found for TPV. While Cronbach’s α was acceptable and comparable for both samples, a significantly lower test-rest-reliability for the BSI was found in the SP sample (rSP = .62; rNSP = .78). Thus, when researching the effects of spiritual practice, one should not only look at differences in means but also consider time stability. We recommend propensity score matching as an alternative for randomization in variables that defy experimental manipulation such as spirituality.

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