Propensity score matching in otolaryngologic literature: A systematic review and critical appraisal

Clinical efficacy of Kuanxiong aerosol for patients with prehospital chest pain: A randomized controlled trial

BACKGROUND

Kuanxiong Aerosol (KXA)(CardioVent®), consisting of Asarum sieboldii Miq. oil, Santalum album L. oil, Alpinia officinarum Hance oil, Piper longum L. oil and borneol, seems to relieve the symptoms of chest pain and serve as a supplementary treatment for prehospital chest pain in emergency department.

STYLE OF THE STUDY

This randomized controlled trial aimed to determine the clinical effect and safety of KXA for patients with prehospital chest pain.

METHODS

A total of 200 patients were recruited from Guangdong Provincial Hospital of Chinese Medicine and randomly divided into KXA group (n = 100) and Nitroglycerin Aerosol (NA) group (n = 100) by SAS 9.2 software. All patients were treated with standardized Western medicine according to the pre-hospital procedure. The experimental group and NA group was additionally treated with KXA and NA respectively. The primary outcome was the relieving time of prehospital chest pain (presented as relief rate) after first-time treatment. The secondary outcomes included the evaluation of chest pain (NRS scores, degree of chest pain, frequency of chest pain after first-time treatment), efficacy in follow-up time (the frequency of average aerosol use, emergency department visits, 120 calls, medical observations and hospitalization at 4 weeks, 8 weeks, 12 weeks), alleviation of chest pain (Seattle angina questionnaire, chest pain occurrence, and degree of chest pain at 12-weeks treatment) and the change of TCM symptoms before and after 12-weeks treatment. In addition, the safety of KXA was also assessed by the occurrence of adverse events. The database was created using Epidata software, and statistical analysis was conducted by SPSS 23.0 software.

RESULTS

A total of 194 participants finally completed the trial, the results showed that after first-time treatment, KXA had a higher relief rate (72.2%) of chest pain within 30 min than that of NA group (59.4%, p = 0.038), KXA group had a lower degree of chest pain (p = 0.005), lower NRS score (p = 0.011) and higher reduction of NRS score (p = 0.005) than the NA. In the follow-up period, KXA group decreased the frequency of 120 call better than that of NA group at 4 weeks (p = 0.040), but KXA had a similar efficacy as NA in the improvement on the of frequency of chest pain, aerosol use, emergency department visits, 120 call, medical observation and hospitalization at 4 weeks, 8 weeks and 12 weeks (p>0.05). There also had no difference between the two groups on the occurrence of chest pain, degree of chest pain, physical limitation, angina stability, treatment satisfaction, and disease perception between the two groups at 12 weeks (p>0.05). In addition, KXA and NA both improved the patient's chest pain, but not the TCM symptoms. In terms of safety, KXA showed similar safety as NA in this study.

CONCLUSIONS

KXA relieved prehospital chest pain faster than NA and had a better remission effect on the prehospital chest pain than that of the NA group in short-period. In long-period, KXA showed similar efficacy on the improvement of prehospital chest pain as NA. KXA may be a safe and reliable therapy for prehospital chest pain.

Lichtenstein versus TIPP versus TAPP versus TEP for primary inguinal hernia, a matched propensity score study on the French Club Hernie Registry

PURPOSE

Groin hernia repair is one of the most frequent operation performed worldwide. Chronic postoperative inguinal pain (CPIP) is the most common and challenging complication after surgical repair with subsequent high socio-economic impact. The aim of this study was to compare the one-year CPIP rates between Lichtenstein, trans-inguinal pre-peritoneal (TIPP), trans-abdominal pre-peritoneal (TAPP) and totally extra-peritoneal (TEP) repair techniques on the French Hernia Registry.

METHODS

Between 2011 and 2021, 15,161 primary groin hernia repairs with 1-year follow-up were available on the register. Using propensity score (PS) matching, matched pairs were formed. Each group was compared in pairs independently; Lichtenstein versus TIPP, TEP and TAPP, TIPP versus TEP and TAPP and finally TEP versus TAPP.

RESULTS

After PS matching analysis, Lichtenstein group showed disadvantage over TIPP, TAPP and TEP groups with significantly more CPIP at one year (15.2% vs 9.6%, p < 0.0001; 15.9% vs. 10.0%, p < 0.0001 and 16.1% vs. 12.4%, p = 0.002, respectively). The 1-year CPIP rates were similar comparing TIPP versus TAPP and TEP groups (9.3% vs 10.5%, p = 0.19 and 9.8% vs 11.8%, p = 0.05, respectively). There was significantly less CPIP rate after TAPP versus TEP repair (1.00% vs 11.9%, p = 0.02).

CONCLUSION

This register-based study confirms the higher CPIP risk after Lichtenstein repair compared to the pre-peritoneal repair techniques. TIPP leads to comparable CPIP rates than TAPP and TEP repairs.

Propensity score matching after multiple imputation when a confounder has missing data

One of the main challenges when using observational data for causal inference is the presence of confounding. A classic approach to account for confounding is the use of propensity score techniques that provide consistent estimators of the causal treatment effect under four common identifiability assumptions for causal effects, including that of no unmeasured confounding. Propensity score matching is a very popular approach which, in its simplest form, involves matching each treated patient to an untreated patient with a similar estimated propensity score, that is, probability of receiving the treatment. The treatment effect can then be estimated by comparing treated and untreated patients within the matched dataset. When missing data arises, a popular approach is to apply multiple imputation to handle the missingness. The combination of propensity score matching and multiple imputation is increasingly applied in practice. However, in this article we demonstrate that combining multiple imputation and propensity score matching can lead to over-coverage of the confidence interval for the treatment effect estimate. We explore the cause of this over-coverage and we evaluate, in this context, the performance of a correction to Rubin's rules for multiple imputation proposed by finding that this correction removes the over-coverage.

A Systematic Review of Propensity Score Matching in the Orthopedic Literature

Background

Propensity score matching (PSM) is a statistical technique used to reduce bias in observational studies by controlling for measured confounders. Given its complexity and popularity, it is imperative that researchers comprehensively report their methodologies to ensure accurate interpretation and reproducibility.

Purpose

This systematic review sought to define how often PSM has been used in recent orthopedic research and to describe how such studies reported their methods. Secondary aims included analyzing study reproducibility, bibliometric factors associated with reproducibility, and associations between methodology and the reporting of statistically significant results.

Methods

PubMed and Embase databases were queried for studies containing "propensity score" and "match*" published in 20 orthopedic journals prior to 2020. All studies meeting inclusion criteria were used for trend analysis. Articles published between 2017 and 2019 were used for analysis of reporting quality and reproducibility.

Results

In all, 261 studies were included for trend analysis, and 162 studies underwent full-text review. The proportion of orthopedic studies using PSM significantly increased over time. Seventy-one (41%) articles did not provide justification for covariate selection. The majority of studies illustrated covariate balance through P values. We found that 19% of the studies were fully reproducible. Most studies failed to report the use of replacement (67.3%) or independent or paired statistical methods (34.0%). Studies reporting standardized mean differences to illustrate covariate balance were less likely to report statistically significant results.

Conclusion

Despite the increased use of PSM in orthopedic research, observational studies employing PSM have largely failed to adequately report their methodology.

Medical Cannabis and Utilization of Nonhospice Palliative Care Services: Complements and Alternatives at End of Life

Background and Objectives

There is a need to know more about cannabis use among terminally diagnosed older adults, specifically whether it operates as a complement or alternative to palliative care. The objective is to explore differences among the terminal illness population within the Illinois Medical Cannabis Program (IMCP) by their use of palliative care.

Research Design and Methods

The study uses primary, cross-sectional survey data from 708 terminally diagnosed patients, residing in Illinois, and enrolled in the IMCP. We compared the sample on palliative care utilization through logistic regression models, examined associations between palliative care and self-reported outcome improvements using ordinary least squares regressions, and explored differences in average pain levels using independent t-tests.

Results

115 of 708 terminally diagnosed IMCP participants were receiving palliative care. We find increased odds of palliative care utilization for cancer (odds ratio [OR] [SE] = 2.15 [0.53], p < .01), low psychological well-being (OR [SE] = 1.97 [0.58], p < .05), medical complexity (OR [SE] = 2.05 [0.70], p < .05), and prior military service (OR [SE] = 2.01 [0.68], p < .05). Palliative care utilization is positively associated with improvement ratings for pain (7.52 [3.41], p < .05) and ability to manage health outcomes (8.29 [3.61], p < .01). Concurrent use of cannabis and opioids is associated with higher pain levels at initiation of cannabis dosing (p < .05).

Discussion and Implications

Our results suggest that cannabis is largely an alternative to palliative care for terminal patients. For those in palliative care, it is a therapeutic complement used at higher levels of pain.