Evolution of bias and sample size in postoperative pain management trials after hip and knee arthroplasty

Risk of serious adverse events associated with non-steroidal anti-inflammatory drugs in orthopaedic surgery. A protocol for a systematic review

BACKGROUND

Postoperative pain is a common condition following orthopaedic surgeries and causes prolonged hospitalisation, delayed rehabilitation and hamper the quality of life. Non-steroidal anti-inflammatory drugs (NSAIDs) are effective analgesics and anti-inflammatory mediators in the treatment of postoperative pain. The association of NSAIDs with serious adverse events may however keep some clinicians and clinical decision makers from using NSAIDs perioperatively. The evidence regarding the risks of serious adverse events following perioperative use of NSAIDs in orthopaedic surgery is sparse and needs to be assessed in a systematic review. This is a protocol for a systematic review that aims to identify the risks of serious adverse events from perioperative use of NSAIDs in orthopaedic patients.

METHODS

Our methodology is based on the Preferred Reporting Items for Systematic Review and Meta-Analysis Protocols and the eight-step assessment procedure suggested by Jakobsen and colleagues. We wish to assess if NSAIDs versus placebo, usual care or no intervention, will influence the risks of serious adverse events in patients undergoing orthopaedic surgery. We will include all randomised trials assessing the use of NSAIDs perioperatively. To identify trials we will search the Medical Literature Analysis and Retrieval System Online, Excerpta Medica database, Cochrane Central Register, Science Citation Index Expanded on Web of Science and BIOSIS. Two authors will screen the literature and extract data. We will use the 'Risk of Bias 2 tool' to assess trials. Extracted data will be analysed using RStudio and Trial Sequential Analysis. We will create a 'Summary of Findings' table in which we will present our primary and secondary outcomes. We will assess the quality of evidence using Grading of Recommendations Assessment, Development and Evaluation (GRADE).

DISCUSSION

This systematic review can potentially aid clinicians and clinical decision makers in the use of NSAIDs for treatment of postoperative pain following orthopaedic surgeries.

Minimal clinically important differences in randomised clinical trials on pain management after total hip and knee arthroplasty: a systematic review

BACKGROUND

Sample size determination is essential for reliable hypothesis testing in clinical trials and should rely on adequate sample size calculations with alpha, beta, variance, and an effect size being the minimal clinically important difference (MCID). This facilitates interpretation of the clinical relevance of statistically significant results. No gold standard for MCIDs exists in postoperative pain research.

METHODS

We searched Cochrane Central Register of Controlled Trials, MEDLINE, and Embase for English language articles on randomised trials investigating analgesic interventions after total hip or knee arthroplasty. Primary outcomes were the reported MCIDs for pain score and cumulated rescue opioid consumption. Secondary outcomes included reported sample size calculations and propensity to report statistical significance without reaching MCID. Trend analyses were conducted using statistical process control.

RESULTS

We included 570 trials. Median MCID for 0-24 h opioid consumption was 10 mg i.v. morphine equivalents for absolute reductions (interquartile range [IQR]: 6.8-14.5) and relative 40% (IQR: 30-50%). Median MCIDs for pain scores were absolute 15 mm at rest (IQR: 10-20) and 18 mm during movement (IQR: 10-20) on a 0-100 mm VAS and relative 30% (IQR: 20-30%). No trends were demonstrated for MCIDs. Adequate sample size calculations were reported in 34% of trials. In 46% of trials with statistically significant primary outcomes, the differences did not reach the predetermined MCID.

CONCLUSIONS

We provide clinician-perceived MCID estimates for rescue opioid consumption and pain scores that can be used for sample size calculations until reliable evidence-based patient-rated MCIDs emerge. Nearly half of the trials with significant findings did not reach the predetermined MCID.

The effect of pre-operative high doses of methylprednisolone on pain management and convalescence after total hip replacement in elderly: a double-blind randomized study

Purpose

The aim of the study was to assess whether administration of a single dose of methylprednisolone in the group patients above 65 years of age will be effective in complex analgesic management after total hip arthroplasty (THA).

Methods

Seventy-seven patients above 65 years old were double-blind randomized into two: the study and controls groups. Pre-operatively, the study group received as a single dose of 125 mg intravenous methylprednisolone, while the others saline solution as placebo. Peri-operatively, all the patients were administered opioid and nonopioid analgesic agents. We measured the levels of inflammatory markers (leukocytosis, C-reactive protein—CRP), pain intensity level (visual analog scale—VAS; numerical rating scale—NRS), the life parameters, and noted complications.

Results

Following administration of methylprednisolone were significantly lower levels of CRP on all the four post-operative days; leukocytosis on the second day; the VAS/NRS score at rest after six, 12, and 18 hours post-operatively, diminished the dose of parenteral opioid preparations (oxycodone hydrochloride), the duration of analgesia by peripheral nerve block was significantly higher as compared with the placebo group (p < 0.000001). No infectious complications were noted; there was one patient who developed post-operative delirium.

Conclusion

A single dose of methylprednisolone significantly reduces the level of post-operative pain at rest on the day of THA in the group patients above 65 years of age, decreases the dose of opioid analgesic agents, and significantly decreases the level of inflammatory markers, without infectious processes.

Trends and predictors of biomedical research quality, 1990-2015: a meta-research study

OBJECTIVE

To measure the frequency of adequate methods, inadequate methods and poor reporting in published randomised controlled trials (RCTs) and test potential factors associated with adequacy of methods and reporting.

DESIGN

Retrospective analysis of RCTs included in Cochrane reviews. Time series describes the proportion of RCTs using adequate methods, inadequate methods and poor reporting. A multinomial logit model tests potential factors associated with methods and reporting, including funding source, first author affiliation, clinical trial registration status, study novelty, team characteristics, technology and geography.

DATA

Risk of bias assessments for random sequence generation, allocation concealment, blinding of participants and personnel, blinding of outcome assessment, incomplete outcome data and selective reporting, for each RCT, were mapped to bibliometric and funding data.

OUTCOMES

Risk of bias on six methodological dimensions and RCT-level overall assessment of adequate methods, inadequate methods or poor reporting.

RESULTS

This study analysed 20 571 RCTs. 5.7% of RCTs used adequate methods (N=1173). 59.3% used inadequate methods (N=12 190) and 35.0% were poorly reported (N=7208). The proportion of poorly reported RCTs decreased from 42.5% in 1990 to 30.2% in 2015. The proportion of RCTs using adequate methods increased from 2.6% in 1990 to 10.3% in 2015. The proportion of RCTs using inadequate methods increased from 54.9% in 1990 to 59.5% in 2015. Industry funding, top pharmaceutical company affiliation, trial registration, larger authorship teams, international teams and drug trials were associated with a greater likelihood of using adequate methods. National Institutes of Health funding and university prestige were not.

CONCLUSION

Even though reporting has improved since 1990, the proportion of RCTs using inadequate methods is high (59.3%) and increasing, potentially slowing progress and contributing to the reproducibility crisis. Stronger incentives for the use of adequate methods are needed.

Bias and sample size in intensive care unit trials: Protocol for a meta-epidemiological study

BACKGROUND

Systematic errors (bias) and random errors result in inflated and imprecise intervention effect estimates in randomised clinical trials (RCT) and meta-analyses. We aim to assess time trends in the Cochrane risk of bias domains and sample size in RCTs of intensive care unit (ICU) interventions.

METHODS AND DESIGN

We will conduct a meta-epidemiologic study of RCTs included in Cochrane systematic reviews assessing any intervention used in adult patients admitted to the ICU. We will search the Cochrane Database of Systematic Reviews and include reviews published from March 2011 corresponding to the latest update in the Cochrane risk of bias tool. We will extract data on risk of bias judgments in the seven Cochrane bias domains and trial sample sizes and evaluate time trends using run charts. The primary outcome will be time trends in the annual proportion of trials with overall low risk of bias (low risk of bias in all bias domains). The secondary outcomes include time trends in the annual median trial sample size, and the annual proportion of trials with low-, unclear- and high risk of bias in each of the seven Cochrane bias domains.

DISCUSSION

The outlined meta-epidemiologic study will assess time trends in risk of bias and sample sizes in RCTs assessing ICU interventions. This will inform researchers, healthcare personnel and policymakers on the general reliability of findings from RCTs of ICU interventions over time, and inform future RCT design and reporting.