Statistics in medical journals: some recent trends

Bacteriuria and phenotypic antimicrobial susceptibility testing in 45 min by point-of-care Sysmex PA-100 System: first clinical evaluation

PURPOSE

This study compared the results of the new Sysmex PA-100 AST System, a point-of-care analyser, with routine microbiology for the detection of urinary tract infections (UTI) and performance of antimicrobial susceptibility tests (AST) directly from urine.

METHODS

Native urine samples from 278 female patients with suspected uncomplicated UTI were tested in the Sysmex PA-100 and with reference methods of routine microbiology: urine culture for bacteriuria and disc diffusion for AST.

RESULTS

The analyser delivered bacteriuria results in 15 min and AST results within 45 min. Sensitivity and specificity for detection of microbiologically confirmed bacteriuria were 84.0% (89/106; 95% CI: 75.6-90.4%) and 99.4% (155/156; 95% CI: 96.5-100%), respectively, for bacterial species within the analyser specifications. These are Escherichia coli, Klebsiella pneumoniae, Proteus mirabilis, Enterococcus faecalis and Staphylococcus saprophyticus, which are common species causing uncomplicated UTI. Overall categorical agreement (OCA) for AST results for the five antimicrobials tested in the Sysmex PA-100 (amoxicillin/clavulanic acid, ciprofloxacin, fosfomycin, nitrofurantoin and trimethoprim) ranged from 85.4% (70/82; 95%CI: 75.9-92.2%) for ciprofloxacin to 96.4% (81/84; 95% CI: 89.9-99.3%) for trimethoprim. The Sysmex PA-100 provided an optimal treatment recommendation in 218/278 cases (78.4%), against 162/278 (58.3%) of clinical decisions.

CONCLUSION

This first clinical evaluation of the Sysmex PA-100 in a near-patient setting demonstrated that the analyser delivers phenotypic AST results within 45 min, which could enable rapid initiation of the correct targeted treatment with no further adjustment needed. The Sysmex PA-100 has the potential to significantly reduce ineffective or unnecessary antibiotic prescription in patients with UTI symptoms.

Statistics in medical research: Common mistakes

The misuse of statistics in medical studies has been discussed extensively with the conclusion that it is both unethical and can have serious clinical consequences. These errors can contribute to incorrect conclusions, compromise the validity of studies, and overestimate or underestimate the effects of treatment. To avoid making these errors, it is critical to consider their presence and understand statistical concepts. This practice will ultimately lead to the use of appropriate statistical techniques for specific research questions and the calculation of an appropriate sample size to guarantee adequate statistical power. Common statistical errors in medical research include sampling bias, the incorrect determination of sample, failing to adjust for multiple comparisons, misinterpreting p-values as a measure of effect size or clinical relevance, choosing incorrect tests for a particular data set, type I and II errors, data fishing, and publication bias. It is important that researchers interpret their results using appropriate statistical concepts by soliciting feedback from specialist statisticians.

High Endplate Hounsfield Units Value Indicate Intervertebral Disc Degeneration Following Transforaminal Lumbar Interbody Fusion Surgery

OBJECTIVE

Lumbar disc degeneration (LDD) is a common cause of low back pain and disability, and its prevalence increases with age. The aim of this study is to investigate whether endplate Hounsfield unit (HU) values have an effect on lumbar disc degeneration (LDD) after transforaminal lumbar interbody fusion (TLIF) surgery in patients with degenerative lumbar stenosis.

METHODS

This study was a retrospective analysis of patients who underwent TLIF surgery in January 2016 to October 2019. One hundred and fifty-seven patients who underwent TLIF surgery for degenerative lumbar stenosis were enrolled in this study. Demographic data was recorded. VAS and ODI values were compared to assess the surgical outcomes in patients with or without process of LDD after TLIF surgery. Correlation analysis was performed to investigate associations between LDD and endplate HU value. Binary logistic regression analysis was carried out to study relationships between the DDD and the multiple risk factors.

RESULTS

There was a statistically significant correlation between LDD, body mass index (BMI), age, paraspinal muscle atrophy, and total endplate scores (TEPS). Also, a strong and independent association between endplate HU value and LDD was found at every lumbar disc level (p < 0.01). After conditioning on matching factors, multivariate logistic regression analysis showed that higher endplate HU (odds ratio [OR]: 1.003, p = 0.003), higher TEPS (OR: 1.264, p = 0.002), higher BMI (odds ratio [OR]: 1.202, p = 0.002), a smaller cross-sectional area (CSA) of the paraspinal muscle preoperatively (OR: 0.096, p < 0.001) were significant predictors of LDD development after TLIF surgery.

CONCLUSIONS

There is a significant association between LDD and endplate HU value after TLIF surgery in patients with degenerative lumbar stenosis. Beyond that, results from this study provide a mechanism by which high endplate HU value predisposes to LDD after TLIF surgery.

Usefulness of automated image analysis for recognition of the fragile X syndrome gestalt in Congolese subjects

BACKGROUND

Computer-aided software such as the facial image diagnostic aid (FIDA) and Face2Gene has been developed to perform pattern recognition of facial features with promising clinical results. The aim of this pilot study was to test Face2Gene's recognition performance on Bantu Congolese subjects with Fragile X syndrome (FXS) as compared to Congolese subjects with intellectual disability but without FXS (non-FXS).

METHOD

Frontal facial photograph from 156 participants (14 patients with FXS and 142 controls) predominantly young-adults to adults, median age 18.9 age range 4-39yo, were uploaded. Automated face analysis was conducted by using the technology used in proprietary software tools called Face2Gene CLINIC and Face2Gene RESEARCH (version 17.6.2). To estimate the statistical power of the Face2Gene technology in distinguishing affected individuals from controls, a cross validation scheme was used.

RESULTS

The similarity seen in the upper facial region (of males and females) is greater than the similarity seen in other parts of the face. Binary comparison of subjects with FXS versus non-FXS and subjects with FXS versus subjects with Down syndrome reveal an area under the curve values of 0.955 (p = 0.002) and 0.986 (p = 0.003).

CONCLUSION

The Face2Gene algorithm is separating well between FXS and Non-FXS subjects.

Highly Sensitive Detection Method of CXCR4 Tumor Hotspot Mutations by Drop-Off Droplet Digital PCR in Patients with IgM Monoclonal Gammopathies

CXCR4 mutations impact disease presentation and treatment outcomes in Waldenström macroglobulinemia. Current techniques used for CXCR4 mutation detection have a number of limitations. The aim of the present study was to develop and analytically validate a novel droplet digital PCR (ddPCR) assay for the simultaneous detection of five of the most common CXCR4 mutations in bone marrow (BM). In silico novel primers and probes designed for simultaneous detection of five hotspot mutations of CXCR4 were first performed. Experimental conditions were optimized, and the assay was analytically validated. The developed assay was further applied in 95 BM samples from patients with IgM gammopathy, 7 BM samples from patients with non-IgM gammopathy and 12 PBMCs from healthy donors, whereas a direct comparison study of Sanger sequencing and allele-specific PCR was performed by using 95 and 39 identical patient tumor DNA samples, respectively. The drop-off ddPCR assay is a robust, cost-effective, highly sensitive, and highly specific screening tool for CXCR4 mutations. Of 95 patients with IgM gammopathy samples, 27 had at least one CXCR4 mutation in their BM samples. With Sanger sequencing, 12 of the 95 samples tested positive, whereas the direct comparison of the developed assay with allele-specific PCR revealed substantial agreement. The clinical performance of the developed assay will be prospectively evaluated in a large number of patients, and the applicability of this assay will be further evaluated.

How Has Statistical Testing in Orthopedics Changed Over Time? An Assessment of High Impact Journals Over 25 Years

BACKGROUND

It is important for physicians to be familiar with statistical techniques commonly used in published medical research. Statistical errors in medical literature are common, and there is a reported lack of understanding regarding statistical knowledge necessary for data interpretation and journal reading. As study design has become increasingly complex, peer-reviewed literature poorly addresses and explains the most common statistical methods utilized across leading orthopedic journals.

METHODS

Articles from 5 leading general and subspecialty orthopedic journals were compiled from 3 distinct time periods. After exclusions were applied, 9521 remained, and a random 5% sampling of these articles, balanced across journals and years, was conducted yielding 437 articles after additional exclusions. Information regarding the number of statistical tests used, power/sample size calculation, type of statistical tests used, level of evidence (LOE), study type, and study design was collected.

RESULTS

The mean number of statistical tests across all 5 orthopedic journals increased from 1.39 to 2.29 by 2018 (p = 0.007). The percentage of articles that reported power/sample size analyses was not found to differ by year, but the value has increased from 2.6% in 1994 to 21.6% in 2018 (p = 0.081). The most commonly used statistical test was the t-test which was present in 20.5% of articles, followed by chi-square test (13%), Mann-Whitney analysis (12.6%) and analysis of variance (ANOVA, 9.6%). The mean number of tests was generally greater in articles from higher impact factor journals (p = 0.013). Studies with a LOE of I used the highest mean number of statistical tests (3.23) compared to studies with lower LOE ratings (range 1.66-2.69, p < 0.001). Randomized control trials used the highest mean number of statistical test (3.31), while case series used the lowest mean number of tests (1.57, p < 0.001).

CONCLUSIONS

The mean number of statistical tests used per article has increased over the past 25 years with the t-test, chi-square test, Mann-Whitney analysis, and ANOVA being the most used statistical tests in leading orthopedic journals. Despite an increase in statistical tests it should be noted that there was a paucity in advance statistical testing within the orthopedic literature. This study displays important trends in data analysis and can serve as a guide to help clinicians and trainees better understand the statistics used in literature as well as identifying deficits within the literature that should be addressed to help progress the field of orthopedics.

A Clinical-Genetic Risk Score for Predicting Cancer-Associated Venous Thromboembolism: A Development and Validation Study Involving Two Independent Prospective Cohorts

PURPOSE

Venous thromboembolism (VTE) is a leading cause of death among patients with cancer. The Khorana score was developed for assessing the risk of VTE in outpatients with cancer receiving chemotherapy, but its accuracy in identifying patients at high risk has been questioned. The aim of this study was to develop and validate a clinical-genetic score that improves the assessment of VTE risk in oncology outpatients within 6 months of diagnosis.

METHODS

The new score was developed using the data of 364 outpatients belonging to the Spanish ONCOTHROMB 12-01 population. In this cohort, clinical data associated with the risk of VTE were collected at the time of diagnosis, including the Khorana score. These patients were also genotyped for the 51 genetic variants known to be associated with VTE. Multivariate logistic regression was performed to determine the weight of each genetic and clinical variable in relation to VTE risk, allowing a clinical-genetic risk score (the ONCOTHROMB score) to be developed. The Khorana and the ONCOTHROMB scores were then compared via the area under the receiver operating characteristic curve (AUC), calibration, and the number of patients needed to treat. The new score was then validated in a study of 263 patients in the Vienna Cancer and Thrombosis Study population.

RESULTS

Nine genetic variants, tumor site, TNM stage, and a body mass index of > 25 kg/m2 were found to be associated with VTE and were used to build the ONCOTHROMB score, which better predicted the overall risk of VTE than did the Khorana score (AUC, 0.781 v 0.580; P < .001). Similar AUC results were recorded in the validation study the Vienna Cancer and Thrombosis Study cohort involving patients with the same type of tumor (AUC for the ONCOTHROMB score v the Khorana score: 0.686 v 0.577; P < .001) and with all type of tumors (AUC for the ONCOTHROMB score v the Khorana score: 0.720 v 0.561; P < .0001).

CONCLUSION

The ONCOTHROMB score for VTE risk in outpatients with cancer, which takes into account both clinical and genetic variables, better identifies patients who might benefit from primary thromboprophylaxis than does the Khorana score.

Neutrophil-to-leukocyte ratio and admission glycemia as predictors of short-term death in very old elderlies with lobar intracerebral hemorrhage

BACKGROUND

The incidence of spontaneous intracerebral hemorrhage (SICH) is highest in very old elderlies (≥75 years). The increasing use of antithrombotic drugs is shifting the epidemiology of SICH towards predominance of lobar subtype, suggesting an incremented propensity of bleeding associated with underlying cerebral amyloid angiopathy. With population aging and antithrombotic use, a parallel raise of proportion of lobar SICH is occurring. Improvement of prognostication in this specific age group and SICH type is needed. Routine blood biomarkers can contribute to prediction of short-term mortality after SICH.

OBJECTIVE

Our aim was to investigate the contribution of routine blood biomarkers for short-term mortality (30-days) in elderly patients with lobar SICH.

METHODS

Retrospective analysis of consecutive 130 patients with ≥ 75 years and lobar SICH. The outcome was 30-day mortality. Logistic regression analysis was used to investigate whether admission routine biomarkers can be used as predictors.

RESULTS

The case fatality was 40.8%. Admission glycaemia level, neutrophil to lymphocyte ratio and mean platelet volume were significantly different between groups (p = 0.001, p = 0.024, p = 0.038, respectively). There was no significant difference in all other routine biomarkers. On multivariate analysis, admission higher mean BG level (odds ratio [OR]: 1.010, 95% confidence interval [CI]: 1.001-1.019, p = 0.026) and neutrophil to lymphocyte ratio (OR: 1.070, 95% CI: 1.008-1.136, p = 0.027) emerged as predictors.

CONCLUSION

In very old patients with lobar SICH, higher BG level and neutrophil to lymphocyte ratio are associated with increased risk of short-term death.

Slipped Capital Femoral Epiphysis, Food Deserts, Poverty, and Urban/Rural Residence: Is There a Link?

BACKGROUND

Childhood obesity is increased in food deserts, a community with little to no access to healthy food. As obesity is associated with slipped capital femoral epiphysis (SCFE), it was the purpose of this study to analyze the prevalence of SCFE patients by food desert location and its interaction with rural/urban location.

METHODS

A retrospective review of all consecutive patients with idiopathic SCFE treated at our institution over 11 years was performed. From the patient's address, the US Census Bureau tract in which the patient resided was determined. Using the census tract code, it was ascertained if the patient lived in a food desert and urban or rural location. Standard statistical analyses were performed; a P <0.05 was considered statistically significant.

RESULTS

There were 177 SCFE patients: 79 girls, 98 boys, 106, White, and 69 nonWhite. The average age at diagnosis was 12.1±1.7 years, the average symptom duration 4.1±5.1 months, and the average weight percentile 94±10. Of these 177 patients, 26.5% lived in a food desert, which was higher than the expected 17.5% ( P =0.023). Those living in a food desert were more commonly nonWhite (60% vs. 32%, P =0.0014). There were 25% from rural areas and 75% from urban areas. No rural SCFE patients lived in food deserts whereas 34% of urban patients lived in food deserts. The average poverty rate of the SCFE patient census tracts was 19%, no greater than the expected 15% ( P =0.32). SCFE patients living in rural census tracts had a lower poverty rate ( P <10 -6 ).

CONCLUSIONS

There is a correlation with the prevalence of SCFE patients by residence in a "food desert", but not with rural/urban locale or poverty status in Indiana. Further research will be needed to see if these findings apply to other states within the United States and other parts of the world.

LEVEL OF EVIDENCE

III.

Non-respondents do not bias outcome assessment after cervical spine surgery: a multicenter observational study from the Norwegian registry for spine surgery (NORspine)

BACKGROUND

The Norwegian registry for spine surgery (NORspine) is a national clinical quality registry which has recorded more than 10,000 operations for degenerative conditions of the cervical spine since 2012. Registries are large observational cohorts, at risk for attrition bias. We therefore aimed to examine whether clinical outcomes differed between respondents and non-respondents to standardized questionnaire-based 12-month follow-up.

METHODS

All eight public and private providers of cervical spine surgery in Norway report to NORspine. We included 334 consecutive patients who were registered with surgical treatment of degenerative conditions in the cervical spine in 2018 and did a retrospective analysis of prospectively collected register data and data on non-respondents' outcomes collected by telephone interviews. The primary outcome measure was patient-reported change in arm pain assessed with the numeric rating scale (NRS). Secondary outcome measures were change in neck pain assessed with the NRS, change in health-related quality of life assessed with EuroQol 5 Dimensions (EQ-5D), and patients' perceived benefit of the operation assessed by the Global Perceived Effect (GPE) scale.

RESULTS

At baseline, there were few and small differences between the 238 (71.3%) respondents and the 96 (28.7%) non-respondents. We reached 76 (79.2%) non-respondents by telephone, and 63 (65.6%) consented to an interview. There was no statistically significant difference between groups in change in NRS score for arm pain (3.26 (95% CI 2.84 to 3.69) points for respondents and 2.77 (1.92 to 3.63) points for telephone interviewees) or any of the secondary outcome measures.

CONCLUSIONS

The results indicate that patients lost to follow-up were missing at random. Analyses of outcomes based on data from respondents can be considered representative for the complete register cohort, if patient characteristics associated with attrition are controlled for.

Gender and Geographic Origin as Determinants of Manuscript Publication Outcomes: JBMR® Bibliometric Analysis from 2017 to 2019

The Journal of Bone and Mineral Research (JBMR®), the flagship journal of the American Society for Bone and Mineral Research (ASBMR), enjoys a premiere position in its field and has a global reach. The journal uses a single-blind peer-review process whereby three editors are typically involved in assessing each submission for publication, in addition to external reviewers. Although emphasizing fairness, rigor, and transparency, this process is not immune to the influence of unconscious biases. The gender and geographic diversity of JBMR® authors, editors, and reviewers has increased over the last three decades, but whether such diversity has affected peer-review outcomes is unknown. We analyzed manuscript acceptance rates based on the gender and geographic origin of authors, reviewers, and Associate Editors. The analysis included 1662 original research articles submitted to JBMR® from September 2017 through December 2019. Gender was assigned using probabilities from an online tool and manually validated through internet searches. Predictor variables of manuscript outcome were determined with multivariate logistic regression analysis. The acceptance rate was highest when the first and last authors were of different genders, and lowest when both authors were men. Reviewer gender did not influence the outcome regardless of the genders of the first and last authors. Associate Editors from all geographical regions tended to select reviewers from their same region. The acceptance rate was highest when the Associate Editor was from Europe. Manuscripts with authors from North America and Australia/New Zealand had greater overall odds of acceptance than those from Europe and Asia. Manuscripts reviewed only by Editorial Board (EB) members had a lower acceptance rate than those refereed by non-EB reviewers or a mix of EB and non-EB reviewers. Overall, the geographical origin of authors, reviewers, and editors, as well as reviewers' EB membership may influence manuscript decisions. Yet, the JBMR® peer-review process remains largely free from gender bias. © 2022 American Society for Bone and Mineral Research (ASBMR).

Practical notes on popular statistical tests in renal physiology

Competent statistical analysis is essential to maintain rigor and reproducibility in physiological research. Unfortunately, the benefits offered by statistics are often negated by misuse or inadequate reporting of statistical methods. To address the need for improved quality of statistical analysis in papers, the American Physiological Society released guidelines for reporting statistics in journals published by the society. The guidelines reinforce high standards for the presentation of statistical data in physiology but focus on the conceptual challenges and, thus, may be of limited use to an unprepared reader. Experimental scientists working in the renal field may benefit from putting the existing guidelines in a practical context. This paper discusses the application of widespread hypothesis tests in a confirmatory study. We simulated pharmacological experiments assessing intracellular calcium in cultured renal cells and kidney function at the systemic level to review best practices for data analysis, graphical presentation, and reporting. Such experiments are ubiquitously used in renal physiology and could be easily translated to other practical applications to fit the reader's specific needs. We provide step-by-step guidelines for using the most common types of t tests and ANOVA and discuss typical mistakes associated with them. We also briefly consider normality tests, exclusion criteria, and identification of technical and experimental replicates. This review is supposed to help the reader analyze, illustrate, and report the findings correctly and will hopefully serve as a gauge for a level of design complexity when it might be time to consult a biostatistician.

Predictive Factors of Return Home and Return to Work for Intensive Care Unit Survivors after Traumatic Brain Injury with a Follow-up Period of 2 Years

Intensive care unit (ICU) survivors after traumatic brain injury (TBI) frequently have serious disabilities with subsequent difficulty in reintegration into society. We aimed to investigate outcomes for ICU survivors after moderate to severe TBI (msTBI) and to identify predictive factors of return home (RH) and return to work (RTW). This single-center retrospective cohort study was conducted on all trauma patients admitted to the emergency ICU of our hospital between 2013 and 2017. Of these patients, adult (age ≥ 18 years) msTBI patients with head Abbreviated Injury Scale ≥ 3 were extracted. We performed univariate/multivariate logistic regression analyses to explore the predictive factors of RH and RTW. Among a total of 146 ICU survivors after msTBI, 107 were included (median follow-up period: 26 months). The RH and RTW rates were 78% and 35%, respectively. Multivariate analyses revealed that the predictive factors of RH were age < 65 years (P < 0.001), HR < 76 bpm (P = 0.015), platelet count ≥ 19 × 10⁴/μL (P = 0.0037), D-dimer < 26 μg/mL (P = 0.034), and Glasgow Coma Scale (GCS) score > 8 (P = 0.0015). Similarly, the predictive factors of RTW were age < 65 years (P < 0.001) and GCS score > 8 (P = 0.0039). This study revealed that “age” and “GCS score on admission” affected RH and RTW for ICU survivors after msTBI.

A feasibility randomised controlled trial of a Fibromyalgia Self-management Programme for adults in a community setting with a nested qualitative study (FALCON)

Background

Fibromyalgia is a condition associated with widespread musculoskeletal pain, fatigue and sleep problems. Fibromyalgia treatment guidelines recommend non-pharmacological interventions and the development of self-management skills. An example of a programme that fits these guidelines is the Fibromyalgia Self-management Programme (FSMP) which consists of one 2.5-hour weekly session over six successive weeks and includes education about fibromyalgia, goal setting, pacing, sleep hygiene and nutritional advice. The FSMP is currently provided in a secondary care hospital setting and co-delivered by a multidisciplinary team. Delivery in a primary care setting has the potential to improve the accessibility of the programme to people with fibromyalgia. Therefore, this feasibility study aimed to determine the practicality and acceptability of conducting a future definitive randomised controlled trial of the FSMP in a community setting.

Method

An exploratory, parallel-arm, one-to-one, randomised controlled trial. Participants were recruited from general practices across South West England, and the FSMP was co-delivered by physiotherapists and occupational therapists across two community sites. To determine the outcome measures for a future definitive trial several were tested. The Revised Fibromyalgia Impact Questionnaire, Arthritis Self-Efficacy Scale-8, Chalder Fatigue Scale, Short form 36, 5-Level EQ-5D version and Jenkins Sleep Scale were collected at baseline, 6 weeks and 6 months. Semi-structured interviews were conducted with patient participants, occupational therapists and physiotherapists to explore the acceptability and feasibility of delivering the FSMP in a community setting.

Results

A total of 74 participants were randomised to the FSMP intervention (n = 38) or control arm (n = 36). Attrition from the trial was 42% (31/74) at 6 months. A large proportion of those randomised to the intervention arm (34%, 13/38) failed to attend any sessions with six of the 13 withdrawing before the intervention commenced. The proportion of missing values was small for each of the outcome measures. Three overarching themes were derived from the interview data; (1) barriers and facilitators to attending the FSMP; (2) FSMP content, delivery and supporting documentation; and (3) trial processes.

Conclusion

It is feasible to recruit people with fibromyalgia from Primary Care to participate in a randomised controlled trial testing the FSMP in a community setting. However, improvement in trial attrition and engagement with the intervention is needed.

Trial registration

The trial is registered with ISRCTN registry and was assigned on 29/04/2019. The registration number is ISRCTN10824225.

Minimal clinically important difference in patients who underwent decompression alone for lumbar degenerative disease

BACKGROUND CONTEXT

The minimal clinically important difference (MCID) represents the smallest change in an outcome measure recognized as clinically meaningful to a patient after receiving a clinical intervention. Most studies that discussed the MCIDs for lumbar spinal stenosis (LSS) included mixed pathologies or procedures despite that the MCID value should be different depending on the intervention. Moreover, despite the efficacy of adopting percentage-change improvement for the MCID threshold, there are limited reports and discussions in the field of lumbar surgery.

PURPOSE

The aim of the present study was to elucidate the MCIDs for the Oswestry Disability Index (ODI), EuroQOL 5-dimension 3-level (EQ-5D-3L), physical component summary (PCS) of the Short Form of the Medical Outcomes Study, and Numeric Rating Scale (NRS) in patients with degenerative LSS treated with decompression surgery without fusion.

STUDY DESIGN/SETTING

A multicenter retrospective cohort study was performed.

PATIENT SAMPLE

A total of 422 patients who underwent decompression surgery for LSS and answered a complete set of questionnaires were included in the study. Patients who underwent endoscopic or revision surgery were excluded.

OUTCOME MEASURES

Preoperative and 1-year postoperative scores of each health-related quality of life questionnaires (HRQOLs) and patient satisfaction questionnaire response METHODS: The patient satisfaction question was used as an anchor, and the cutoff values were estimated based on absolute point improvement from baseline using a receiver-operating characteristic (ROC) curve analysis and the "mean change" method for MCIDs. The MCID values for percentage-change in HRQOLs were also calculated using ROC curve analysis. The three cutoff values for each HRQOL were validated using the Youden index for determining the most robust MCIDs.

RESULTS

Of the patients, 356 (84.4%) were at least "somewhat satisfied" with the treatment results. The two cutoff values of absolute point-change in each HRQOL, which were estimated by two different anchor-based methods, were similar. The area under the curve of the ROC curve for percentage-change tended to be higher than that for absolute point-change. Moreover, the Youden index of the percentage-change in each HRQOL was higher than that of the absolute point-change calculated by either the "mean change" method or the ROC curve analysis. Based on these results, it was proposed that MCID was 42.4% for percentage-change in ODI, 22.0% for EQ-5D-3L, 13.7% for PCS, 25.0% for NRS (low back pain), 55.6% for NRS (leg pain), 22.2% for NRS (leg numbness).

CONCLUSIONS

The MCIDs of HRQOLs were calculated in patients with LSS treated with decompression surgery without concomitant fusion procedure. The MCID cutoffs based on percentage-change from baseline were more effective than those of absolute point-change.

Intention to Exclusively Breastfeed Is Associated with Lower Rates of Cesarean Section for Nonmedical Reasons in a Cohort of Mothers in Vietnam

Background: Breastfeeding brings benefits to both mothers and children in the short term and long term. Unnecessary cesarean sections can bring risks to both parties. This study was undertaken to examine the relationship between exclusive breastfeeding intention and cesarean delivery. Methods: We analyzed data collected from 554 single mothers who delivered in Dong Anh General District Hospital or Hanoi Obstetrics and Gynecology Hospital, Vietnam, in 2020–2021. The relationship between exclusive breastfeeding intention and cesarean delivery for nonmedical reasons was adjusted for maternal education, maternal age, parity, history of fetal loss, having at least eight antenatal contacts, hospital of delivery, child sex, and birth weight. Results: Antenatally, 34.8% (184/529) of mothers intended to breastfeed exclusively until 6 months and 30.8% (84/274) underwent cesarean section for a nonmedical reason. After adjusting for other factors, mothers who intended to breastfeed exclusively until 6 months were less likely to undergo cesarean delivery for nonmedical reasons (OR = 0.55, 95% CI: 0.31–0.96, p = 0.034). Conclusions: This study adds to the growing evidence related to unnecessary cesarean sections and routine over-medicalization of normal birth in the urban areas of Vietnam. The association between breastfeeding intentions and a lower rate of cesarean section suggests that education on breastfeeding could be a useful intervention for reducing the rate of cesarean sections and improving maternal and child health.

The reporting of p values, confidence intervals and statistical significance in Preventive Veterinary Medicine (1997-2017)

Background

Despite much discussion in the epidemiologic literature surrounding the use of null hypothesis significance testing (NHST) for inferences, the reporting practices of veterinary researchers have not been examined. We conducted a survey of articles published in Preventive Veterinary Medicine, a leading veterinary epidemiology journal, aimed at (a) estimating the frequency of reporting p values, confidence intervals and statistical significance between 1997 and 2017, (b) determining whether this varies by article section and (c) determining whether this varies over time.

Methods

We used systematic cluster sampling to select 985 original research articles from issues published in March, June, September and December of each year of the study period. Using the survey data analysis menu in Stata, we estimated overall and yearly proportions of article sections (abstracts, results-texts, results-tables and discussions) reporting p values, confidence intervals and statistical significance. Additionally, we estimated the proportion of p values less than 0.05 reported in each section, the proportion of article sections in which p values were reported as inequalities, and the proportion of article sections in which confidence intervals were interpreted as if they were significance tests. Finally, we used Generalised Estimating Equations to estimate prevalence odds ratios and 95% confidence intervals, comparing the occurrence of each of the above-mentioned reporting elements in one article section relative to another.

Results

Over the 20-year period, for every 100 published manuscripts, 31 abstracts (95% CI [28–35]), 65 results-texts (95% CI [61–68]), 23 sets of results-tables (95% CI [20–27]) and 59 discussion sections (95% CI [56–63]) reported statistical significance at least once. Only in the case of results-tables, were the numbers reporting p values (48; 95% CI [44–51]), and confidence intervals (44; 95% CI [41–48]) higher than those reporting statistical significance. We also found that a substantial proportion of p values were reported as inequalities and most were less than 0.05. The odds of a p value being less than 0.05 (OR = 4.5; 95% CI [2.3–9.0]) or being reported as an inequality (OR = 3.2; 95% CI [1.3–7.6]) was higher in the abstracts than in the results-texts. Additionally, when confidence intervals were interpreted, on most occasions they were used as surrogates for significance tests. Overall, no time trends in reporting were observed for any of the three reporting elements over the study period.

Conclusions

Despite the availability of superior approaches to statistical inference and abundant criticism of its use in the epidemiologic literature, NHST is substantially the most common means of inference in articles published in Preventive Veterinary Medicine. This pattern has not changed substantially between 1997 and 2017.

Bystander interventions and survival after exercise-related sudden cardiac arrest: a systematic review

OBJECTIVE

To evaluate the provision of bystander interventions and rates of survival after exercise-related sudden cardiac arrest (SCA).

DESIGN

Systematic review.

DATA SOURCES

MEDLINE, EMBASE, PubMed, CINAHL, SPORTDiscus, Cochrane Library and grey literature sources were searched from inception to November/December 2020.

STUDY ELIGIBILITY CRITERIA

Observational studies assessing a population of exercise-related SCA (out-of-hospital cardiac arrests that occurred during exercise or within 1 hour of cessation of activity), where bystander cardiopulmonary resuscitation (CPR) and/or automated external defibrillator (AED) use were reported, and survival outcomes were ascertained.

METHODS

Among all included studies, the median (IQR) proportions of bystander CPR and bystander AED use, as well as median (IQR) rate of survival to hospital discharge, were calculated.

RESULTS

A total of 29 studies were included in this review, with a median study duration of 78.7 months and a median sample size of 91. Most exercise-related SCA patients were male (median: 92%, IQR: 86%-96%), middle-aged (median: 51, IQR: 39-56 years), and presented with a shockable arrest rhythm (median: 78%, IQR: 62%-86%). Bystander CPR was initiated in a median of 71% (IQR: 59%-87%) of arrests, whereas bystander AED use occurred in a median of 31% (IQR: 19%-42%) of arrests. Among the 19 studies that reported survival to hospital discharge, the median rate of survival was 32% (IQR: 24%-49%). Studies which evaluated the relationship between bystander interventions and survival outcomes reported that both bystander CPR and AED use were associated with survival after exercise-related SCA.

CONCLUSION

Exercise-related SCA occurs predominantly in males and presents with a shockable ventricular arrhythmia in most cases, emphasising the importance of rapid access to defibrillation. Further efforts are needed to promote early recognition and a rapid bystander response to exercise-related SCA.

Determination of MYD88L265P mutation fraction in IgM monoclonal gammopathies

Quantitative evaluation of the tumor load in patients with IgM monoclonal gammopathies in tDNA and cfDNA samples.

We describe a novel method for the detection of MYD88^L265P mutation using a competitive allele-specific polymerase chain reaction (Cast-PCR) assay. This assay has a sensitivity of 1 × 10⁻³, is applicable in reactions containing very low amounts of DNA (as low as 20 pg), and allowed the detection of MYD88^L265P somatic mutation in both tumor-derived DNA (tDNA) and cell-free DNA (cfDNA). In addition, using the Cast-PCR assay, we were able to determine the mutation allele fraction (MAF) in each tested sample. We then analyzed baseline tDNA and cfDNA samples from 163 patients (53 with immunoglobulin M monoclonal gammopathy of undetermined significance and 110 with Waldenström’s macroglobulinemia [WM], of whom 54 were asymptomatic and 56 were symptomatic) and also in sequential samples of 37 patients. MAF in both cfDNA and tDNA was higher among patients with symptomatic compared with asymptomatic WM and in those with asymptomatic WM compared with those with immunoglobulin M (IgM) monoclonal gammopathy of undetermined significance. In addition, the evaluation of sequential samples showed that MAF decreased after treatment, whereas it increased in patients who relapsed or progressed to symptomatic WM. Thus, Cast-PCR is a highly sensitive, cost-effective diagnostic tool for MYD88^L265P detection, applicable in both tDNA and cfDNA samples, that also provides a quantitative evaluation of the tumor load in patients with IgM monoclonal gammopathies.

Development of a rapid lateral flow immunochromatography assay for the detection of group-specific antibodies against VP7 protein of bluetongue virus in multiple species

Bluetongue virus (BTV), the causative agent of bluetongue disease infects many domestic and wild ruminants. In the present study, colloidal gold nanoparticle-based lateral flow immunochromatography assay (LFIA) was developed to detect the group-specific antibodies to BTV in serum samples of sheep, goats, cattle, and camel. The recombinant VP7 protein of BTV conjugated to colloidal gold nanoparticles (GNPs) was used as a detector reagent. Recombinant streptococcal protein G and monoclonal antibody to BTV group-specific antigen were immobilized as the test and the control line, respectively on a nitrocellulose membrane. The protein G could capture the specific antibodies to BTV present in the serum of multiple ruminant species susceptible to BTV in a common test format and could eliminate the requirement of multiple anti-species antibodies. Upon addition of serum sample, GNP-rVP7 protein-serum complex migrated laterally onto the strip via capillary action and results were analyzed based on appearance of red colour band at test and control line. Serum samples (n = 481) of sheep, goats, cattle, and camel segregated as positive and negative by the commercial competitive-ELISA (c-ELISA) kit were tested in the fabricated LFIA strips to analyze the performance of the assay. In comparison with c-ELISA, the relative diagnostic sensitivity (DSn) of 95.2% with 91.6-97.6 (95%)) confidence interval and relative diagnostic specificity (DSp) of 99.6% 97.8-100.0 (95%) confidence interval were obtained for the optimized LFIA. The agreement between the LFIA and the c-ELISA was excellent as indicated by the kappa coefficient value of 0.949 (SE = 0.0142) with 0.9219 to 0.9779 (95%) confidence interval. The recombinant protein G based LFIA is a sensitive, specific, rapid, one-step test that can be used in the field or poorly equipped laboratories for serological diagnosis and serosurveillance of bluetongue in multiple susceptible species.

Persistent Hypertension Up to One Year Postpartum among Women with Hypertensive Disorders in Pregnancy in a Low-Resource Setting: A Prospective Cohort Study

Background

Hypertensive disorders in pregnancy (HDPs) are associated with lifelong cardiovascular disease risk. Persistent postpartum hypertension in HDPs could suggest progression to chronic hypertension. This phenomenon has not been well examined in low- and middle-income countries (LIMCs), and most previous follow-ups typically last for maximally six weeks postpartum. We assessed the prevalence of persistent hypertension up to one year in women with HDPs in a low resource setting and determined associated risk factors.

Methodology

A prospective cohort study of women conducted at eight tertiary health care facilities in seven states of Nigeria. Four hundred and ten women with any HDP were enrolled within 24 hours of delivery and followed up at intervals until one year postpartum. Descriptive statistics were performed to express the participants' characteristics. Univariable and multivariable logistic regressions were conducted to identify associated risk factors.

Results

Of the 410 women enrolled, 278 were followed up to one year after delivery (follow-up rate 68%). Among women diagnosed with gestational hypertension and pre-eclampsia/eclampsia, 22.3% (95% CI; 8.3-36.3) and 62.1% (95% CI; 52.5-71.9), respectively, had persistent hypertension at six months and this remained similar at one year 22.3% (95% CI; 5.6-54.4) and 61.2% (95% CI; 40.6-77.8). Maternal age and body mass index were significant risk factors for persistent hypertension at one year [aORs = 1.07/year (95% CI; 1.02-1.13) and 1.06/kg/m2 (95% CI; 1.01-1.10)], respectively.

Conclusion

This study showed a substantial prevalence of persistent hypertension beyond puerperium. Health systems in LMICs need to be organized to anticipate and maintain postpartum monitoring until blood pressure is normalized, or women referred or discharged to family physicians as appropriate. In particular, attention should be given to women who are obese, and or of higher maternal age.

Bayesian Hodges-Lehmann tests for statistical equivalence in the two-sample setting: Power analysis, type I error rates and equivalence boundary selection in biomedical research

BACKGROUND

Null hypothesis significance testing (NHST) is among the most frequently employed methods in the biomedical sciences. However, the problems of NHST and p-values have been discussed widely and various Bayesian alternatives have been proposed. Some proposals focus on equivalence testing, which aims at testing an interval hypothesis instead of a precise hypothesis. An interval hypothesis includes a small range of parameter values instead of a single null value and the idea goes back to Hodges and Lehmann. As researchers can always expect to observe some (although often negligibly small) effect size, interval hypotheses are more realistic for biomedical research. However, the selection of an equivalence region (the interval boundaries) often seems arbitrary and several Bayesian approaches to equivalence testing coexist.

METHODS

A new proposal is made how to determine the equivalence region for Bayesian equivalence tests based on objective criteria like type I error rate and power. Existing approaches to Bayesian equivalence testing in the two-sample setting are discussed with a focus on the Bayes factor and the region of practical equivalence (ROPE). A simulation study derives the necessary results to make use of the new method in the two-sample setting, which is among the most frequently carried out procedures in biomedical research.

RESULTS

Bayesian Hodges-Lehmann tests for statistical equivalence differ in their sensitivity to the prior modeling, power, and the associated type I error rates. The relationship between type I error rates, power and sample sizes for existing Bayesian equivalence tests is identified in the two-sample setting. Results allow to determine the equivalence region based on the new method by incorporating such objective criteria. Importantly, results show that not only can prior selection influence the type I error rate and power, but the relationship is even reverse for the Bayes factor and ROPE based equivalence tests.

CONCLUSION

Based on the results, researchers can select between the existing Bayesian Hodges-Lehmann tests for statistical equivalence and determine the equivalence region based on objective criteria, thus improving the reproducibility of biomedical research.

Evaluation of Inter-Observer Reliability of Animal Welfare Indicators: Which Is the Best Index to Use?

Simple Summary

In order to be effective, on-farm welfare assessment protocols should always rely on reliable, as well as valid and feasible, indicators. Inter-observer reliability refers to the extent to which two or more observers are observing and recording data in the same way. The present study focuses on the problem of assessing inter-observer reliability in the case of dichotomous (e.g., yes/no) welfare indicators and the presence of two observers, in order to decide about the inclusion of indicators in welfare assessment protocols. We compared the performance of the most popular currently available agreement indexes. Some widely used indexes showed their inappropriateness to evaluate the inter-observer reliability when the agreement between observers was high. Other less used indexes, such as Bangdiwala’s B or Gwet’s γ(AC1), were found to perform better and are therefore suggested to assess the inter-observer reliability of dichotomous indicators.

Abstract

This study focuses on the problem of assessing inter-observer reliability (IOR) in the case of dichotomous categorical animal-based welfare indicators and the presence of two observers. Based on observations obtained from Animal Welfare Indicators (AWIN) project surveys conducted on nine dairy goat farms, and using udder asymmetry as an indicator, we compared the performance of the most popular agreement indexes available in the literature: Scott’s π, Cohen’s k, kPABAK, Holsti’s H, Krippendorff’s α, Hubert’s Γ, Janson and Vegelius’ J, Bangdiwala’s B, Andrés and Marzo’s ∆, and Gwet’s γ(AC1). Confidence intervals were calculated using closed formulas of variance estimates for π, k, kPABAK, H, α, Γ, J, ∆, and γ(AC1), while the bootstrap and exact bootstrap methods were used for all the indexes. All the indexes and closed formulas of variance estimates were calculated using Microsoft Excel. The bootstrap method was performed with R software, while the exact bootstrap method was performed with SAS software. k, π, and α exhibited a paradoxical behavior, showing unacceptably low values even in the presence of very high concordance rates. B and γ(AC1) showed values very close to the concordance rate, independently of its value. Both bootstrap and exact bootstrap methods turned out to be simpler compared to the implementation of closed variance formulas and provided effective confidence intervals for all the considered indexes. The best approach for measuring IOR in these cases is the use of B or γ(AC1), with bootstrap or exact bootstrap methods for confidence interval calculation.

Bibliometric Analysis of the English Musculoskeletal Literature over the Last 30 Years

Publication and authorship are important in academia for career advancement, obtaining grants, and improved patient care. There has been a recent interest in bibliometric changes over time, especially regarding the gender gap. The purpose of this study was to explore bibliometric changes in the musculoskeletal literature. Bibliometric variables (number of authors, institutions, countries, pages, references, corresponding author position, author gender, geographic region of origin, and editorial board makeup) were analyzed for 5 basic science and 12 clinically oriented musculoskeletal journals from 1985 through 2016. Statistical analyses comprised bivariate analyses, multifactorial ANOVAs, and logistic regression analyses. A p < 0.005 was considered significant. Nearly, all variables increased over time. Asia had the highest number of authors and corresponding author positions, Australia/New Zealand the highest number of institutions and references, North America the highest number of pages, and Europe the highest number of countries. Those with a female first author had more authors, institutions, countries, references, and pages. Likewise, those with a female corresponding author had more authors, institutions, countries, references, and pages. Single-authored manuscripts decreased over time. The percentage of female first authors rose from 10.8% in 1985-1987 to 23.7% in 2015-2016. There were more female 1^st authors in the basic science journals compared to the clinical journals (33.2% vs. 12.7%). Single-authored manuscripts were more likely to be written by males (5.1 vs. 2.4%) and decreased over time. The many differences by geographic region of origin likely reflect different socio/cultural attitudes regarding academia and research, as well as the gender composition of the disciplines by geographic region. Overall, there has been an increase in the number of female 1^st and corresponding authors, editorial board members, and chief editors, indicating a slow but progressive narrowing of the gender gap.

Preoperative Stratification of Liver Transplant Recipients: Validation of the LTRS

BACKGROUND

The liver transplant risk score (LTRS) was developed to stratify 90-day mortality of patients referred for liver transplantation (LT). We aimed to validate the LTRS using a new cohort of patients.

METHODS

The LTRS stratifies the risk of 90-day mortality of LT recipients based on their age, body mass index, diabetes, model for end-stage liver disease (MELD) score, and need for dialysis. We assessed the performance of the LTRS using a new cohort of patients transplanted in the United States between July 2013 and June 2017. Exclusion criteria were age <18 years, ABO incompatibility, redo or multivisceral transplants, partial grafts, malignancies other than hepatocellular carcinoma and fulminant hepatitis.

RESULTS

We found a linear correlation between the number of points of the LTRS and 90-day mortality. Among 18 635 recipients, 90-day mortality was 2.7%, 3.8%, 5.2%, 4.8%, 6.7%, and 9.3% for recipients with 0, 1, 2, 3, 4, and ≥5 points (P < 0.001). The LTRS also stratified 1-year mortality that was 5.5%, 7.7%, 9.9%, 9.3%, 10.8%, and 15.4% for 0, 1, 2, 3, 4, and ≥5 points (P < 0.001). An inverse correlation was found between the LTRS and 4-year survival that was 82%, 79%, 78%, 82%, 78%, and 66% for patients with 0, 1, 2, 3, 4, and ≥5 points (P < 0.001). The LTRS remained an independent predictor after accounting for recipient sex, ethnicity, cause of liver disease, donor age, cold ischemia time, and waiting time.

CONCLUSIONS

The LTRS can stratify the short- and long-term outcomes of LT recipients at the time of their evaluations irrespective of their gender, ethnicity, and primary cause of liver disease.

Doug Altman: Driving critical appraisal and improvements in the quality of methodological and medical research

Doug Altman was a visionary leader and one of the most influential medical statisticians of the last 40 years. Based on a presentation in the "Invited session in memory of Doug Altman" at the 40th Annual Conference of the International Society for Clinical Biostatistics (ISCB) in Leuven, Belgium and our long-standing collaborations with Doug, we discuss his contributions to regression modeling, reporting, prognosis research, as well as some more general issues while acknowledging that we cannot cover the whole spectrum of Doug's considerable methodological output. His statement "To maximize the benefit to society, you need to not just do research but do it well" should be a driver for all researchers. To improve current and future research, we aim to summarize Doug's messages for these three topics.

The epidemiology of tuberculosis-associated hyperglycemia in individuals newly screened for type 2 diabetes mellitus: systematic review and meta-analysis

Background

There is scarce evidence that tuberculosis (TB) can cause diabetes in those not previously known to be diabetic. Whilst the World Health Organization (WHO) recommends screening for Diabetes Mellitus (DM) at the onset of TB treatment, nevertheless, it remains to be elucidated which patients with TB-associated hyperglycemia are at higher risk for developing DM and stand to benefit from a more regular follow-up. This review aims to firstly quantify the reduction of newly detected hyperglycemia burden in TB patients who are on treatment over time; secondly, determine the burden of TB-associated hyperglycemia after follow-up, and thirdly, synthesize literature on risk factors for unresolved TB-associated hyperglycemia in previously undiagnosed individuals.

Methods

We searched PUBMED, EMBASE, SCOPUS, and Global Health for articles on TB-associated hyperglycemia up to September 30th, 2019. Search terms included Tuberculosis and hyperglycemia/DM, and insulin resistance. We appraised studies, extracted data, and conducted a meta-analysis to assess the change of the burden of hyperglycemia in prospective studies. The review is registered in the PROSPERO database (CRD42019118173).

Results

Eleven studies were included in the meta-analysis yielding a total of 677 (27,3%) of patients with newly detected hyperglycemia at baseline. The mean quality score of eligible studies using the Newcastle-Ottawa Quality Assessment Scale was 7.1 out of 9 (range 6-9). The pooled unresolved new cases of hyperglycemia at the end of follow up was 50% (95% CI: 36–64%) and the total pooled burden of hyperglycemia at 3–6 months of follow up was 11% (95% CI: 7–16%), with both estimates displaying a high heterogeneity, which remained significant after performing a sub-analysis by DM diagnostic method and 3 months of follow up. As only 2 studies explored risk factors for unresolved hyperglycemia, no meta-analysis was performed on risk factors.

Conclusion

Our meta-analysis showed that although in half of the patients with newly observed hyperglycemia at baseline, it remained unresolved at a follow-up of 3 to 6 months, the total burden of hyperglycemia is slightly above 10%, 3 months after initiating TB treatment. Studies are warranted to assess whether risk factors including HIV positivity, smoking, and extensive pulmonary TB disease put patients at higher risk for DM.

Supplementary information

Supplementary information accompanies this paper at 10.1186/s12879-020-05512-7.

Oral non-steroidal anti-inflammatory drugs versus other oral analgesic agents for acute soft tissue injury

BACKGROUND

Acute soft tissue injuries are common and costly. The best drug treatment for such injuries is not certain, although non-steroidal anti-inflammatory drugs (NSAIDs) are often recommended. There is concern about the use of oral opioids for acute pain leading to dependence. This is an update of a Cochrane Review published in 2015.

OBJECTIVES

To assess the benefits or harms of NSAIDs compared with other oral analgesics for treating acute soft tissue injuries.

SEARCH METHODS

We searched the CENTRAL, 2020 Issue 1, MEDLINE (from 1946), and Embase (from 1980) to January 2020; other databases were searched to February 2019.

SELECTION CRITERIA

We included randomised or quasi-randomised controlled trials involving people with acute soft tissue injury (sprain, strain, or contusion of a joint, ligament, tendon, or muscle occurring within 48 hours of inclusion in the study), and comparing oral NSAIDs versus paracetamol (acetaminophen), opioid, paracetamol plus opioid, or complementary and alternative medicine. The outcomes were pain, swelling, function, adverse effects, and early re-injury.

DATA COLLECTION AND ANALYSIS

Two review authors independently assessed studies for eligibility, extracted data, and assessed risk of bias. We assessed the quality of the evidence using GRADE methodology.

MAIN RESULTS

We included 20 studies, with 3305 participants. Three studies included children only. The others included predominantly young adults; approximately 60% were male. Seven studies recruited people with ankle sprains only. Most studies were at low or unclear risk of bias; however, two were at high risk of selection bias, three were at high risk of bias from lack of blinding, and five were at high risk of selective outcome reporting bias. Some evidence relating to pain relief was high certainty. Other evidence was either moderate, low or very low certainty, reflecting study limitations, indirectness, imprecision, or combinations of these. Thus, we are certain or moderately certain about some of the estimates, and uncertain or very uncertain of others. Eleven studies, involving 1853 participants compared NSAIDs with paracetamol. There were no differences between the two groups in pain at one to two hours (1178 participants, 6 studies; high-certainty evidence), at days one to three (1232 participants, 6 studies; high-certainty evidence), and at day seven or later (467 participants, 4 studies; low-certainty evidence). There was little difference between the groups in numbers of participants with minimal swelling at day seven or later (77 participants, 1 study; low-certainty evidence). Very low-certainty evidence from three studies (386 participants) means we are uncertain of the finding of little difference between the two groups in return to function at day seven or later. There was low-certainty evidence from 10 studies (1504 participants) that NSAIDs may slightly increase the risk of gastrointestinal adverse events compared with paracetamol. There was low-certainty evidence from nine studies (1679 participants) of little difference in neurological adverse events between the NSAID and paracetamol groups. Six studies, involving 1212 participants compared NSAIDs with opioids. There was moderate-certainty evidence of no difference between the groups in pain at one hour (1058 participants, 4 studies), and low-certainty evidence for no difference in pain at days four or seven (706 participants, 1 study). There was very low-certainty evidence of no important difference between the groups in swelling (84 participants, 1 study). Participants in the NSAIDs group were more likely to return to function in 7 to 10 days (542 participants, 2 studies; low-certainty evidence). There was moderate-certainty evidence (1143 participants, 5 studies) that NSAIDs were less likely to result in gastrointestinal or neurological adverse events compared with opioids. Four studies, involving 240 participants, compared NSAIDs with the combination of paracetamol and an opioid. The applicability of findings from these studies is in question because the dextropropoxyphene combination analgesic agents used are no longer in general use. Very low-certainty evidence means we are uncertain of the findings of no differences between the two interventions in the numbers with little or no pain at day one (51 participants, 1 study), day three (149 participants, 2 studies), or day seven (138 participants, 2 studies); swelling (230 participants, 3 studies); return to function at day seven (89 participants, 1 study); and the risk of gastrointestinal or neurological adverse events (141 participants, 3 studies). No studies reported re-injury rates. No studies compared NSAIDs with oral complementary and alternative medicines, AUTHORS' CONCLUSIONS: Compared with paracetamol, NSAIDs make no difference to pain at one to two hours and at two to three days, and may make no difference at day seven or beyond. NSAIDs may result in a small increase in gastrointestinal adverse events and may make no difference in neurological adverse events compared with paracetamol. Compared with opioids, NSAIDs probably make no difference to pain at one hour, and may make no difference at days four or seven. NSAIDs probably result in fewer gastrointestinal and neurological adverse effects compared with opioids. The very low-certainly evidence for all outcomes for the NSAIDs versus paracetamol with opioid combination analgesics means we are uncertain of the findings of no differences in pain or adverse effects. The current evidence should not be extrapolated to adults older than 65 years, as this group was not well represented in the studies.

Bibliometric and authorship trends over a 30 year publication history in two representative US sports medicine journals

Bibliometric studies are important to understand changes and improvement opportunities in academia. This study compared bibliometric trends for two major sports medicine/arthroscopy journals, the American Journal of Sports Medicine® (AJSM®) and Arthroscopy® over the past 30 years. Trends over time and comparisons between both journals were noted for common bibliometric variables (number of authors, references, pages, citations, and corresponding author position) as well as author gender and continental origin. Appropriate statistical analyses were performed. A p < 0.001 was considered statistically significant. One representative year per decade was used. There were 814 manuscripts from AJSM® and 650 from Arthroscopy®. For AJSM® the number of manuscripts steadily increased from 86 in 1986 to 350 in 2016; for Arthroscopy® the number of manuscripts increased from 73 in 1985/1986, to 267 in 2006, but then dropped to 229 in 2016. There were significant increases in all bibliometric variables, except for the number of citations which decreased in Arthroscopy®. There were significant differences in manuscript region of origin by journal (p = 0.000002). Arthroscopy® had a greater percentage of manuscripts from Asia than AJSM® (19.3% vs 11.5%) while AJSM® had a greater percentage from North America (70.3% vs 59.2%); both journals had similar percentages from Europe (18.2% for AJSM® and 21.6% for Arthroscopy®). For AJSM® the average percentage of female first authors was 13.3%, increasing from 4.7% in 1986 to 19.3% in 2016; the average percentage of female corresponding authors was 7.3%. For Arthroscopy®, the average percentage of female first authors was 8.1%, increasing from 2.8% in 1985/1986 to 15.7% in 2016 (p = 0.00007). In conclusion, AJSM® and Arthroscopy® showed an increase in most variables analyzed. Although Arthroscopy® is climbing at a higher rate than AJSM® for female authors, AJSM® has an overall greater percentage of female authors.

Reporting of data analysis methods in psychiatric journals: Trends from 1996 to 2018

OBJECTIVES

The article aims to evaluate how study designs and data analysis methods in psychiatric studies have changed over the last 22 years.

METHODS

This study involved a total of 320 papers published in 1996 and 2018 in the American Journal of Psychiatry, Acta Psychiatrica Scandinavica, British Journal of Psychiatry, and JAMA Psychiatry. We manually reviewed the articles to determine the way in which they reported the study characteristics and the methods applied in data analysis.

RESULTS

The statistical intensity in psychiatric journals has changed over the past 20 years. Traditional methods of testing statistical significance were widely used both in 1996 and in 2018. In 2018, there was an increase in reporting more complex methods, such as multivariable regression models, multilevel modelling, and intracluster correlation methods. However, computationally complex data mining or machine learning procedures were not adopted by psychiatric researchers.

CONCLUSION

The increase in statistical intensity in the literature suggests that readers of prominent psychiatric journals must possess a substantial level of statistical expertise if they wish to critically evaluate the findings published in these journals. It is essential to include an awareness of this substantial change in data analysis methods in psychiatric undergraduate and postgraduate education.

Association of Appendicular Lean Mass, and Subcutaneous and Visceral Adipose Tissue With Mortality in Older Brazilians: The São Paulo Ageing & Health Study

Body composition changes as a result of ageing may impact the survival of older adults. However, its influence on mortality risk is uncertain. Currently, the best method for body composition analysis in clinical practice is DXA. Nonetheless, the few studies on body composition by DXA and mortality risk in the elderly have some limitations. We investigated the association between body composition by DXA and mortality in a cohort of elderly subjects. Eight hundred thirty-nine community-dwelling subjects (516 women, 323 men) ≥ 65 years of age were assessed by a questionnaire, clinical data, laboratory exams, and body composition by DXA at baseline. Total fat and its components (eg, visceral adipose tissue [VAT]) were estimated. Appendicular lean mass (ALM) adjusted for fat and ALM divided by height² was used to ascertain the presence of low muscle mass (LMM). Mortality was recorded during follow-up. Multivariate logistic regression was used to compute ORs for all-cause and cardiovascular mortality. Over a mean follow-up of 4.06 ± 1.07 years, there were 132 (15.7%) deaths. In men, after adjustment for relevant variables, the presence of LMM (OR, 11.36, 95% CI, 2.21 to 58.37, P = 0.004) and VAT (OR, 1.99, 95% CI, 1.38 to 2.87, P < 0.001, for each 100-g increase) significantly increased all-cause mortality risk, whereas total fat, measured by the fat mass index, was associated with decreased mortality risk (OR, 0.48, 95% CI, 0.33 to 0.71, P < 0.001). Similar results were observed for cardiovascular mortality. In women, only LMM was a predictor of all-cause (OR, 62.88, 95% CI, 22.59 to 175.0, P < 0.001) and cardiovascular death (OR, 74.54, 95% CI, 9.72 to 571.46, P < 0.001). LMM ascertained by ALM adjusted for fat and fat mass by itself are associated with all-cause and cardiovascular mortality risk in the elderly. Visceral and subcutaneous fat have opposite roles on mortality risk in elderly men. Thus, DXA is a promising tool to estimate risk of mortality in the elderly. © 2019 American Society for Bone and Mineral Research.

Relationship between Highly Active Antiretroviral Therapy (HAART) and human papillomavirus type 16 (HPV 16) infection among women in Sub-Saharan Africa and public health implications: A systematic review

Invasive cervical cancer is the most prevalent cancer among women in Sub-Saharan Africa. In 2013, the World Health Organization (WHO) emitted recommendations to start Highly Active Antiretroviral Therapy (HAART) regardless of CD4 count. Although HAART has been shown to reduce the prevalence of high-risk human papillomavirus (HR-HPV) genotypes, it is unclear whether it confers a protective effect specifically for HPV 16. This review summarizes the existing evidence regarding the effect of HAART on HPV 16 infection, as this genotype may not be influenced by immunity level and explores its implications for Sub Saharan Africa. A comprehensive literature review was undertaken and quality assessment was carried out on the selected papers. Four cohort studies and three cross-sectional studies were identified for which the overall quality score assessment ranged from weak/moderate (Score of 1.8) to strong (Score of 3). The evidence yielded by our review was conflicting. Thus, the high heterogeneity between study populations and results did not allow us to draw any firm conclusions as to whether HAART has an impact on HPV 16 acquisition/prevalence. As only three studies were conducted in Africa, there are insufficient grounds for solid comparison between geographic regions. In light of inadequate data, HPV unvaccinated women on HAART should still receive more frequent follow-up.

What is the Natural History of the Triangular Fibrocartilage Complex Tear Without Distal Radioulnar Joint Instability?

BACKGROUND

The triangular fibrocartilage complex (TFCC) tear is a common cause of ulnar-side wrist pain; however, its natural course is not well understood.

QUESTIONS/PURPOSES

We sought (1) to determine the natural course of TFCC tears without distal radioulnar joint (DRUJ) instability, and (2) to identify the factors associated with poor prognosis after nonsurgical treatment of TFCC tears.

METHODS

Over a 3-year period, we treated 117 patients with TFCC tears who did not have DRUJ instability. The diagnosis was made on the basis of ulnar-sided wrist pain, a positive ulnocarpal stress test or ulnar grinding test, and identification of a tear on MRI or CT arthrography. Of those, 25 were excluded during the initial evaluation period because they met the previously defined indications of surgery on the basis of clinical history. Another 19 patients (20%) were lost to followup before 6 months, and one patient was excluded because of prior wrist surgery, leaving 72 wrists in 72 patients for analysis in this retrospective study, which drew data from a review of electronic medical records of one institution. The group consisted of 42 men and 30 women, with a mean age of 40 years (range, 18-70 years). The study group was followed for a mean of 16 months (range, 6 to 36 months). We evaluated the pain VAS and patient-rated wrist evaluation (PRWE) at the initial visit, at 4, 8, and 12 weeks, and at more than 6 months after the initial visit. A PRWE score ≤ 20 points indicated complete recovery, and a PRWE score more than 20 points was considered an incomplete recovery. We used Kaplan-Meier survival analysis and Cox regression modelling to estimate the time to complete recovery and to identify factors associated with incomplete recovery among the seven possible factors of older age (≥ 45 years), male, obesity (body mass index ≥ 30 kg/m), dominant-hand involvement, chronic symptoms (≥ 6 months), traumatic tear, and ulnar-plus variance.

RESULTS

The Kaplan-Meier survival analysis showed that estimated cumulative incidence of complete recovery was 30% (95% confidence interval [CI], 20-40) at 6 months and 50% (95% CI, 39-61) at 1 year. We could not find any risk factors among the seven candidate factors, including older age (hazard ratio [HR], 0.608; 95% CI, 0.34-1.087; p = 0.093), male (HR, 1.152; 95% CI, 0.667-1.991; p = 0.612), obesity (HR, 1.433; 95% CI, 0.603-3.402; p = 0.415), dominant hand involvement (HR, 1.808; 95% CI, 0.927-3.527; p = 0.082), chronic symptoms (HR, 0.763; 95% CI, 0.443-1.922; p = 0.133), traumatic tear (HR, 0.756; 95% CI, 0.432-1.32; p = 0.325), and ulnar plus variance (HR, 0.804; 95% CI, 0.461-1.404; p = 0.443).

CONCLUSIONS

This study demonstrates that nonsurgical treatment is moderately successful for treating patients with TFCC tears without DRUJ instability. We recommend a minimum of 6 months nonsurgical treatment as the first-line treatment for this injury. Future studies are necessary to clarify predictors of persistent pain with nonsurgical treatment to avoid an unnecessary surgical delay.

LEVEL OF EVIDENCE

Level III, prognostic study.

Reporting data analysis methods in high-impact respiratory journals

Data analysis methods play an important role in respiratory research. We evaluated the application and complexity of data analytical methods in high-impact respiratory journals and compared the statistical reporting in these respiratory articles with reports published in other eminent medical journals. This study involved a total of 160 papers published in 2015 in the European Respiratory Journal, American Journal of Respiratory and Critical Care Medicine, Chest and Thorax, and 680 papers published between 2007-2015 in other medical journals including the Lancet and New England Journal of Medicine. We manually reviewed the articles to determine the way in which they reported the methods applied in data analysis. The statistical intensity in the respiratory journals was equal to that in eminent medical journals. Traditional ways of testing statistical significance were widely used in respiratory articles. Statistical procedures were not always described in sufficient detail, and the prominent respiratory journals did not display different profiles with respect to their statistical content. Readers of the prominent respiratory journals need to possess a substantial level of statistical expertise if they wish to critically evaluate the design, methodology, data analysis and interpretation of the findings published in these journals.

Treatment strategy and long-term functional outcome of traumatic elbow dislocation in childhood: a single centre study

PURPOSE

Traumatic elbow dislocation (TED) is the most common injury of large joints in children. There is an ongoing debate on the optimal treatment for TED. We aimed to assess the functional outcome after operative and nonoperative treatment of TED.

METHODS

We analysed the medical records of patients with TED treated at the University Children's Hospital, Basel, between March 2006 and June 2015. Functional outcome was assessed using the Mayo Elbow Performance Score (MEPS) and Quick Disabilities of the Arm, Shoulder and Hand (QuickDASH) Sport and Music Module score. These scores were compared between nonoperatively and operatively treated patients.

RESULTS

A total of 37 patients (mean age 10.2 years, 5.2 to 15.3) were included. Of these, 21 (56.8%) children had undergone nonoperative treatment, with 16 (43.2%) patients having had operative treatment. After a mean follow-up of 5.6 years (1.2 to 5.9), MEPS and QuickDASH Sport and Music Module scores in the nonoperative group and operative group were similar: MEPS: 97.1 points (SD 4.6) versus 97.2 points (SD 2.6); 95% confidence interval (CI)-2.56 to 2.03); p = 0.53; QuickDASH Sport and Music Module score: 3.9 points (SD 6.1) versus 3.1 points (SD 4.6); 95% CI 2.60 to 4.17; p = 0.94. We noted no significant differences regarding the long-term functional outcome between the subgroup of children treated operatively versus those treated nonoperatively for TED with accompanying fractures of the medial epicondyle and medial condyle.

CONCLUSION

Functional outcome after TED was excellent, independent of the treatment strategy. If clear indications for surgery are absent, a nonoperative approach for TED should be considered.

LEVEL OF EVIDENCE

Level III - therapeutic, retrospective, comparative study.

Does Walkability Contribute to Geographic Variation in Psychosocial Distress? A Spatial Analysis of 91,142 Members of the 45 and Up Study in Sydney, Australia

Walkability describes the capacity of the built environment to promote walking, and has been proposed as a potential focus for community-level mental health planning. We evaluated this possibility by examining the contribution of area-level walkability to variation in psychosocial distress in a population cohort at spatial scales comparable to those used for regional planning in Sydney, Australia. Data on psychosocial distress were analysed for 91,142 respondents to the 45 and Up Study baseline survey between January 2006 and April 2009. We fit conditional auto regression models at the postal area level to obtain smoothed “disease maps” for psychosocial distress, and assess its association with area-level walkability after adjusting for individual- and area-level factors. Prevalence of psychosocial distress was 7.8%; similar for low (7.9%), low-medium (7.9%), medium-high (8.0%), and high (7.4%) walkability areas; and decreased with reducing postal area socioeconomic disadvantage: 12.2% (most), 9.3%, 7.5%, 5.9%, and 4.7% (least). Unadjusted disease maps indicated strong geographic clustering of psychosocial distress with 99.0% of excess prevalence due to unobserved and spatially structured factors, which was reduced to 55.3% in fully adjusted maps. Spatial and unstructured variance decreased by 97.3% and 39.8% after adjusting for individual-level factors, and another 2.3% and 4.2% with the inclusions of area-level factors. Excess prevalence of psychosocial distress in postal areas was attenuated in adjusted models but remained spatially structured. Postal area prevalence of high psychosocial distress is geographically clustered in Sydney, but is unrelated to postal area walkability. Area-level socioeconomic disadvantage makes a small contribution to this spatial structure; however, community-level mental health planning will likely deliver greatest benefits by focusing on individual-level contributors to disease burden and inequality associated with psychosocial distress.

Safety and improvement of movement function after stroke with atomoxetine: A pilot randomized trial

Background: Intensive, task-oriented motor training has been associated with neuroplastic reorganization and improved upper extremity movement function after stroke. However, to optimize such training for people with moderate-to-severe movement impairment, pharmacological modulation of neuroplasticity may be needed as an adjuvant intervention.

Objective: Evaluate safety, as well as improvement in movement function, associated with motor training paired with a drug to upregulate neuroplasticity after stroke.

Methods: In this double-blind, randomized, placebo-controlled study, 12 subjects with chronic stroke received either atomoxetine or placebo paired with motor training. Safety was assessed using vital signs. Upper extremity movement function was assessed using Fugl-Meyer Assessment, Wolf Motor Function Test, and Action Research Arm Test at baseline, post-intervention, and 1-month follow-up.

Results: No significant between-groups differences were found in mean heart rate (95% CI, –12.4–22.6; p = 0.23), mean systolic blood pressure (95% CI, –1.7–29.6; p = 0.21), or mean diastolic blood pressure (95% CI, –10.4–13.3; p = 0.08). A statistically significant between-groups difference on Fugl-Meyer at post-intervention favored the atomoxetine group (95% CI, 1.6–12.7; p = 0.016).

Conclusion: Atomoxetine combined with motor training appears safe and may optimize motor training outcomes after stroke.

Medical student researchers in Colombia and associated factors with publication: a cross-sectional study

BACKGROUND

Gaps between evidence-based research and clinical-public health practice have been evident for decades. One of the aims of medical student research is to close this gap. Accordingly, evaluating individual and environmental factors that influence participation of medical students in research are needed to understand and identify potential targets for action. This study aims to identify characteristics of medical student researchers in Colombia and the associated factors with scientific publications.

METHODS

A cross-sectional study of Colombian medical students involved in research using a validated, self-administered, online survey. The survey was distributed through the Colombian Association of Medical Students' Associations (ASCEMCOL). Data sets were analyzed using descriptive and summary statistics. Bivariate analysis and a multiple logistic regression model were conducted to identify predictors of scientific publications.

RESULTS

A total of 133 responses were analyzed from students at 12 Colombian cities and 20 higher-education institutions. Although 94% of responders had at least one research proposal, only 57% had completed a project, and 17% had published their findings. Barriers for undertaking research included time restrictions and a lack of mentorship. Motivational factors included opportunity to publish findings and good mentorship. Students planning to do a specialization (OR = 3.25; 95% Confidence interval [CI] = 1.27-8.30), innovators (OR = 3.52; 95%CI = 1.30-9.52) and committed (OR = 3.39; 95%CI = 1.02-11.29), those who had previously published their findings (OR 9.13 IC95% 2.57-32.48), and were further in their medical education (OR 2.26 IC95% 1.01-5.07), were more likely to publish scientific papers.

CONCLUSIONS

Our findings describe medical students understanding of the process of conducting research in Colombia. Although there appears to be motivation to participate in research, very few students achieve publication. Barriers such as time constraints and mentorship seem to play a critical role. This highlights opportunities where barriers to research can be overcome in medical school and other levels.

An instrument to assess the statistical intensity of medical research papers

Background

There is widespread evidence that statistical methods play an important role in original research articles, especially in medical research. The evaluation of statistical methods and reporting in journals suffers from a lack of standardized methods for assessing the use of statistics. The objective of this study was to develop and evaluate an instrument to assess the statistical intensity in research articles in a standardized way.

Methods

A checklist-type measure scale was developed by selecting and refining items from previous reports about the statistical contents of medical journal articles and from published guidelines for statistical reporting. A total of 840 original medical research articles that were published between 2007–2015 in 16 journals were evaluated to test the scoring instrument. The total sum of all items was used to assess the intensity between sub-fields and journals. Inter-rater agreement was examined using a random sample of 40 articles. Four raters read and evaluated the selected articles using the developed instrument.

Results

The scale consisted of 66 items. The total summary score adequately discriminated between research articles according to their study design characteristics. The new instrument could also discriminate between journals according to their statistical intensity. The inter-observer agreement measured by the ICC was 0.88 between all four raters. Individual item analysis showed very high agreement between the rater pairs, the percentage agreement ranged from 91.7% to 95.2%.

Conclusions

A reliable and applicable instrument for evaluating the statistical intensity in research papers was developed. It is a helpful tool for comparing the statistical intensity between sub-fields and journals. The novel instrument may be applied in manuscript peer review to identify papers in need of additional statistical review.

Associations between highly active antiretroviral therapy and the presence of HPV, premalignant and malignant cervical lesions in sub-Saharan Africa, a systematic review: current evidence and directions for future research

OBJECTIVES

In sub-Saharan Africa, substantial international funding along with evidence-based clinical practice have resulted in an unparalleled scale-up of access to antiretroviral treatment at a higher CD4 count. The role and timing of highly active antiretroviral therapy (HAART) in mediating cervical disease remains unclear. The aim of this article is to systematically review all evidence pertaining to Africa and identify research gaps regarding the epidemiological association between HAART use and the presence of premalignant/malignant cervical lesions.

METHOD

Five databases were searched until January 2017 to retrieve relevant literature from sub-Saharan Africa. Publications were included if they addressed prevalence, incidence or clearance of human papillomavirus (HPV) infection in women undergoing HAART as well as cytological or histological neoplastic abnormalities.

RESULTS

22 studies were included, of which seven were prospective studies. Women receiving HAART are less likely to develop squamous intraepithelial lesions (SILs). There is evidence that duration of HAART along with the CD4 count may reduce the prevalence of high-risk HPV (HR-HPV), suggesting that without HAART, severe immunosuppression increases the risk of becoming or remaining infected with HR-HPV. Furthermore, according to existent literature, the CD4 count, rather than HAART coverage or its duration, plays a central role in the prevalence of cervical intraepithelial neoplasia (CIN) 2 and CIN 3.

CONCLUSION

Our findings suggest a positive impact of HAART duration, in conjunction and interaction with CD4 count, on reducing the prevalence of HR-HPV. The greatest treatment effect might be seen among women starting at the lowest CD4 count, which may have a more instrumental role in cervical oncogenesis than either HAART use or the treatment duration on the prevalence of CIN 2 and CIN 3. There is still insufficient evidence to show a clear association between HAART coverage and the incidence of invasive cervical cancer. Enhanced surveillance on the impact of HAART treatment is crucial.

Reporting of Bayesian analysis in epidemiologic research should become more transparent

OBJECTIVES

The objective of this systematic review is to investigate the use of Bayesian data analysis in epidemiology in the past decade and particularly to evaluate the quality of research papers reporting the results of these analyses.

STUDY DESIGN AND SETTING

Complete volumes of five major epidemiological journals in the period 2005-2015 were searched via PubMed. In addition, we performed an extensive within-manuscript search using a specialized Java application. Details of reporting on Bayesian statistics were examined in the original research papers with primary Bayesian data analyses.

RESULTS

The number of studies in which Bayesian techniques were used for primary data analysis remains constant over the years. Though many authors presented thorough descriptions of the analyses they performed and the results they obtained, several reports presented incomplete method sections and even some incomplete result sections. Especially, information on the process of prior elicitation, specification, and evaluation was often lacking.

CONCLUSION

Though available guidance papers concerned with reporting of Bayesian analyses emphasize the importance of transparent prior specification, the results obtained in this systematic review show that these guidance papers are often not used. Additional efforts should be made to increase the awareness of the existence and importance of these checklists to overcome the controversy with respect to the use of Bayesian techniques. The reporting quality in epidemiological literature could be improved by updating existing guidelines on the reporting of frequentist analyses to address issues that are important for Bayesian data analyses.

A multilevel modelling solution to mathematical coupling

Owing to mathematical coupling, statistical analyses relating change to baseline values using correlation or regression are erroneous, where the statistical procedure of testing the null hypothesis becomes invalid. Alternatives, such as Oldham’s method and the variance ratio test, have been advocated, although these are limited in the presence of measurement errors with non-constant variance. Furthermore, such methods prohibit the consideration of additional covariates (e.g., treatment group within trials) or confounders (e.g., age and gender). This study illustrates the more sophisticated approach of multilevel modelling (MLM) which overcomes these limitations and provides a comprehensive solution to the analysis of change with respect to baseline values. Although mathematical coupling is widespread throughout applied research, one particular area where several studies have suggested a strong relationship between baseline disease severity and treatment effect is guided tissue regeneration (GTR) within dental research. For illustration, we use GTR studies where the original data were found to be available in the literature for reanalysis. We contrast the results from an MLM approach and Oldham’s method with the standard (incorrect) approach that suffers from mathematical coupling. MLM provides a robust solution when relating change to baseline and is capable of simultaneously dealing with complex error structures and additional covariates and/or potential confounders.

Preoperative predictors for outcomes after total hip replacement in patients with osteoarthritis: a systematic review

BACKGROUND

This systematic review examines which patient related factors influence functional and clinical outcomes after total hip arthroplasty (THA) in patients with hip osteoarthritis (OA).

METHODS

We performed a systematic review according to the PRISMA guidelines. We searched databases and trial registries for prospective studies including OA patients who underwent primary THA. Studies with preoperative measurements on predictors, with at least 1 year follow-up were included. Risk of bias and confounding was assessed for two domains: follow-up rate and looking at independent effects.

RESULTS

Thirty-five studies were included (138,039 patients). Only nine studies (29 %) had low risk of bias for all domains thus suggesting an overall low quality of evidence. Studies were heterogeneous in the predictors tested and in the observed directions of the associations. Overall, preoperative function (13 studies (37 %), 2 with low risk of bias) and radiological OA (6 studies (17 %), 1 with low risk of bias) were predictors with the most consistent findings. Worse preoperative function and more severe radiological OA were associated with larger postoperative improvement. However, these patients never reached the level of postoperative functioning as patients with better preoperative function or less severe radiological OA. For age, gender, comorbidity, pain and quality of life the results of studies were conflicting. For BMI, some studies (n = 5, 2 with low risk of bias) found worse outcomes for patients with higher BMI. However, substantial improvement was still achieved regardless of their BMI.

CONCLUSION

There is not enough evidence to draw succinct conclusions on preoperative predictors for postoperative outcome in THA, as results of studies are conflicting and the methodological quality is low. Results suggest to focus on preoperative function and radiological osteoarthritis to decide when THA will be most effective. The present mapping of current evidence on the relationship between patient related factors and outcomes provides better information compared to individual studies and may help to set patient expectations before surgery. In addition, these findings may contribute to discussions on how to achieve the best possible postoperative outcome for specific patient groups.

TRIAL REGISTRATION

This systematic review was registered in Prospero, registration number RD42014009977 .

Vapocoolants (cold spray) for pain treatment during intravenous cannulation

BACKGROUND

Intravenous cannulation is a painful procedure that can provoke anxiety and stress. Injecting local anaesthetic can provide analgesia at the time of cannulation, but it is a painful procedure. Topical anaesthetic creams take between 30 and 90 minutes to produce an effect. A quicker acting analgesic allows more timely investigation and treatment. Vapocoolants have been used in this setting, but studies have reported mixed results.

OBJECTIVES

To determine effects of vapocoolants on pain associated with intravenous cannulation in adults and children. To explore variables that might affect the performance of vapocoolants, including time required for application, distance from the skin when applied and time to cannulation. To look at adverse effects associated with the use of vapocoolants.

SEARCH METHODS

We searched the Cochrane Central Register of Controlled Trials (CENTRAL), MEDLINE, EMBASE, Latin American Caribbean Health Sciences Literature (LILACS), the Cumulative Index to Nursing and Allied Health Literature (CINAHL), the Institute for Scientific Information (ISI) Web of Science and the http://clinicaltrials.gov/, http://www.controlled-trials.com/ and http://www.trialscentral.org/ databases to 1 May 2015. We applied no language restrictions. We also scanned the reference lists of included papers.

SELECTION CRITERIA

We included all blinded and unblinded randomized controlled trials (RTCs) comparing any vapocoolant with placebo or control to reduce pain during intravenous cannulation in adults and children.

DATA COLLECTION AND ANALYSIS

Three review authors independently assessed trial quality and extracted data, contacted study authors for additional information and assessed included studies for risk of bias. We collected and analysed data for the primary outcome of pain during cannulation, and for the secondary outcomes of pain associated with application of the vapocoolant, first attempt success rate of intravenous cannulation, adverse events and participant satisfaction. We performed subgroup analyses for the primary outcome to examine differences based on age of participant, type of vapocoolant used, application time of vapocoolant and clinical situation (emergency vs elective). We used random-effects model meta-analysis in RevMan 5.3 and assessed heterogeneity between trial results by examining forest plots and calculating the I(2) statistic.

MAIN RESULTS

We found nine suitable studies of 1070 participants and included them in the qualitative analyses. We included eight studies of 848 participants in the meta-analysis for the primary outcome (pain during intravenous cannulation). Use of vapocoolants resulted in a reduction in pain scores as measured by a linear 100 mm visual analogue scale (VAS 100) compared with controls (difference between means -12.5 mm, 95% confidence interval (CI) -18.7 to -6.4 mm; moderate-quality evidence). We could not include in the meta-analysis one study, which showed no effects of the intervention.Use of vapocoolants resulted in increased pain scores at the time of application as measured by a VAS 100 compared with controls (difference between means 6.3 mm, 95% CI 2.2 to 10.3 mm; four studies, 461 participants; high-quality evidence) and led to no difference in first attempt success compared with controls (risk ratio (RR) 1.00, 95% CI 0.94 to 1.06; six studies, 812 participants; moderate-quality evidence). We documented eight minor adverse events reported in 279 vapocoolant participants (risk difference (RD) 0.03, 95% CI 0 to 0.05; five studies, 551 participants; low quality-evidence).The overall risk of bias of individual studies ranged from low to high, with high risk of bias for performance and detection bias in four studies. Sensitivity analysis showed that exclusion of studies at high or unclear risk of bias did not materially alter the results of this review.

AUTHORS' CONCLUSIONS

Moderate-quality evidence indicates that use of a vapocoolant immediately before intravenous cannulation reduces pain during the procedure. Use of vapocoolant does not increase the difficulty of cannulation nor cause serious adverse effects but is associated with mild discomfort during application.

Basics, common errors and essentials of statistical tools and techniques in anesthesiology research

The statistical portion is a vital component of any research study. The research methodology and the application of statistical tools and techniques have evolved over the years and have significantly helped the research activities throughout the globe. The results and inferences are not accurately possible without proper validation with various statistical tools and tests. The evidencebased anesthesia research and practice has to incorporate statistical tools in the methodology right from the planning stage of the study itself. Though the medical fraternity is well acquainted with the significance of statistics in research, there is a lack of in-depth knowledge about the various statistical concepts and principles among majority of the researchers. The clinical impact and consequences can be serious as the incorrect analysis, conclusions, and false results may construct an artificial platform on which future research activities are replicated. The present tutorial is an attempt to make anesthesiologists aware of the various aspects of statistical methods used in evidence-based research and also to highlight the common areas where maximum number of statistical errors are committed so as to adopt better statistical practices.