Unstandardized Mean Difference Research Articles

The Effect of Probiotic Yogurt on Glycemic Control in Type 2 Diabetes or Obesity: A Meta-Analysis of Nine Randomized Controlled Trials.

Probiotic yogurt is suggested as a nutritional approach in type 2 diabetes (T2D) and obesity. We performed a systematic review and meta-analysis of randomized controlled trials (RCTs) evaluating the effects of probiotic yogurt on glycemic outcomes in T2D or obesity. The databases used to search for RCTs included Medline and Scopus. The RCTs were eligible if outcomes included selected glycemic markers. In nine eligible trials, 237 and 235 subjects were in treatment (probiotic yogurt) and control (mostly conventional yogurt) groups, respectively. There was no significant difference for pooled unstandardized mean difference (USMD) hemoglobin A1c (HbA1c) by probiotic yogurt compared with the control in T2D (USMD: −0.366; 95% CI: −0.755, 0.024, p = 0.066) and obesity (USMD: 0.116, 95% CI: −0.007, 0.238, p = 0.065). Similarly, there were no effects of probiotic yogurt on fasting blood glucose, fasting insulin, or insulin resistance (estimated by homeostatic model assessment of insulin resistance (HOMA-IR)) in either T2D or obesity. In conclusion, the present meta-analysis has not demonstrated the benefits of consuming probiotic compared with conventional yogurt for improving glucose control in patients with diabetes or obesity. Larger trials are needed to verify the benefits of probiotic and/or conventional yogurt or other probiotic fermented milk (e.g., kefir) on glycemic markers in patients with diabetes and obesity.

Neutrophil Lymphocyte Ratio and Cardiovascular Disease Risk: A Systematic Review and Meta-Analysis.

Objective This systematic review aimed to measure the association between neutrophil lymphocyte ratio (NLR) and cardiovascular disease (CVD) risk. Methods Relevant studies were identified from Medline and Scopus databases. Observational studies with NLR as a study factor were eligible for review. The outcomes of interest were any type of CVD including acute coronary syndrome, coronary artery disease, stroke, or a composite of these cardiovascular events. Mean differences in NLR between CVD and non-CVD patients were pooled using unstandardized mean difference (USMD). Odds ratios of CVD between high and low NLR groups were pooled using a random effects model. Results Thirty-eight studies (n=76,002) were included. High NLR was significantly associated with the risks of CAD, ACS, stroke, and composite cardiovascular events with pooled ORs of 1.62 (95% CI: 1.38-1.91), 1.64 (95% CI: 1.30, 2.05), 2.36 (95% CI: 1.44, 2.89), and 3.86 (95% CI: 1.73, 8.64), respectively. In addition, mean NLRs in CAD, ACS, and stroke patients were significantly higher than in control groups. Conclusion High NLR was associated with CAD, ACS, stroke, and composite cardiovascular events. Therefore, NLR may be a useful CVD biomarker.

Sodium removal by peritoneal dialysis: a systematic review and meta-analysis.

Achievement of sodium and fluid balance is considered a major determinant of dialysis adequacy in peritoneal dialysis (PD). However, the contribution of different PD modalities to dialytic sodium removal (DSR) remains ill-defined. We performed a systematic review and meta-analysis to compare DSR by manual (continuous ambulatory PD, CAPD) versus automated PD (APD). Alternative PD strategies to remove sodium were also analyzed. Seven cohort studies, including 683 patients, 406 in CAPD and 277 in APD, were meta-analyzed out of the 30 studies selected based on DSR data availability. Overall, the unstandardized mean difference between CAPD and APD was significant [- 56mmol/day (95% CI - 106, - 6), p = 0.027]. Heterogeneity was high (I2 87.2%; p < 0.001). Meta-regression showed a strict correlation of DSR difference with creatinine dialysate/plasma ratio (D/P) (p = 0.04). DSR was significantly lower in APD than CAPD [86.2 (57.3-115.1) vs. 141.3 (107.6-174.9) mmol/day, p = 0.015]. Conversely, ultrafiltration (UF) did not differ [1122.6 (891.2-1354.0) in CAPD and 893.6 (823.0-964.2) ml/day in APD, p = 0.064]. A very strong correlation between DSR and achieved UF was found in CAPD (R = 0.94; p < 0001) while no relationship was detected in APD (R = - 0.07; p = 0.85). CAPD allows a higher DSR than APD, even though UF is not different. APD removes more water than sodium; therefore, DSR should be measured rather than estimated from the achieved UF. The difference in DSR between the two modalities decreases in high transporters. Novel strategies proposed to increase DSR, e.g. lower sodium dialysate or adapted-APD, are promising, but ad hoc studies are necessary.

Comparative outcomes of epidural steroids versus placebo after lumbar discectomy in lumbar disc herniation: a systematic review and meta-analysis of randomized controlled trials.

Treatment for lumbar disc herniation after failed conservative treatment is discectomy. Discectomy can significantly relieve back pain as well as radicular symptoms. However, many patients with lumbar discectomy experience moderate-to-severe back pain and radicular leg pain. The results of application of epidural steroids (ES) for pain management after lumbar discectomy have previously been inconclusive. We have conducted a systematic review and meta-analysis aims to compare outcomes (efficacy and complications) of epidural steroid application and placebo after discectomy in lumbar disc herniation. This systematic review was conducted according to the Preferred Reporting Items for Systematic Reviews and Meta-Analyses guidelines. Relevant studies that reported visual analog scale of back and leg pain, morphine consumption, hospital stay and post-operative complications of either group were identified from Medline and Scopus from the date of inception to 28 October 2017. A total of 12 studies were pooled and analysed, with nine studies having undergone conventional discectomy and three studies having undergone minimally invasive surgery (MIS) discectomy. Overall, there were 1006 patients (502 in the ES group and 504 in the placebo group) included. The unstandardized mean difference of VAS of back pain at 1week and 1month, leg pain at 1week and 1month, morphine consumption and hospital stay was -0.53 (95% CI -1.42, 0.36) score, -0.89 (95% CI -1.36, -0.42) score, -0.63 (95% CI -0.75, -0.50) score, -0.47 (95% CI -0.78, -0.15) score, -8.47 (95% CI -16.16, -0.78) mg and -0.89 (95% CI -1.49, -0.30) days lower when compared to placebo after lumbar discectomy in patients with lumbar disc herniation. A total of ten studies compared the ratio of complication between the ES and placebo groups. No significant differences were noted for complications within the two groups (0.92; 95% CI 0.47, 1.83). This meta-analysis analysed lower back and leg pain, morphine consumption and hospital stay, with no significant difference in complications for ES application after lumbar discectomy in lumbar disc herniation. In terms of surgical approaches with MIS compared to conventional approach, this review demonstrates that ES can reduce post-operative morphine consumption when the surgical approach is conventional, but not for MIS.Level of evidence I.

Vitamin D ameliorates systolic but not diastolic blood pressure in patients with type 2 diabetes: Results from a meta-analysis of randomized controlled trials.

Inconsistent findings have been reported regarding the effects of vitamin D on blood pressure in patients with type 2 diabetes (T2D). This study aimed to evaluate the subject through a meta-analysis. A computerized literature search on five databases was performed and randomized controlled trials (RCTs) published until March 2016 were identified. The eligibility criteria for articles to be selected were parallel-group RCTs in which consumption of a kind of vitamin D was compared with placebo in patients with T2D. Un-standardized mean difference and its corresponding 95 % confidence interval (CI) was calculated from the effect sizes by using random effects model. Studies comparing intervention group (received vitamin D) with control group (received placebo) were enrolled in meta-analysis. Meta-analysis on 26 studies with 1789 type 2 diabetic subjects showed that vitamin D significantly reduced systolic blood pressure (SBP; -0.97 mmHg, 95 % CI: -1.94, -0.001, P = 0.050), but not diastolic blood pressure (DBP; -0.10 mmHg, 95 % CI: -0.22, 0.02, P = 0.087). Subgroup analyses showed that administration of vitamin D in patients with baseline serum 25-hydroxy vitamin D < 50 nmol/l and baseline SBP < 140 mmHg significantly reduced SBP. Moreover, the patients who received vitamin D without Ca co-supplementation showed significant reduction in SBP. Vitamin D doses (≤ 2000 or > 2000 IU/day) and method of vitamin D application (Supplementation or food fortification) did not affect the blood pressure. This study demonstrated that vitamin D improved SBP in type 2 diabetic patients. Therefore, this vitamin can be considered as an adjuvant therapy in these patients.

Effect of Chlorella supplementation on cardiovascular risk factors: A meta-analysis of randomized controlled trials

The effect of Chlorella supplementation on cardiovascular risk factors of subjects with different health status has not been conclusively studied. Therefore, the efficacy of Chlorella supplementation on cardiovascular risk factors was assessed through a meta-analysis. A literature search on five electronic databases was performed and related randomized controlled trials (RCTs) published until 15 January 2017 were identified. For each study, the effect size of each outcome was presented as Un-standardized mean difference and 95% confidence interval (CI). The overall effect for each outcome was calculated using random effects model. Meta-analysis on 19 RCTs with 797 subjects indicated that Chlorella administration significantly decreased the levels of total cholesterol (TC;-9.09mg/dl, 95% CI:-12.91 to-5.26, P<0.001), low-density lipoprotein cholesterol (LDL-C;-8.32mg/dl, 95% CI:-12.22 to-4.42, P<0.001), systolic blood pressure (SBP;-4.51mmHg, 95% CI:-6.53 to-2.48, P<0.001), diastolic blood pressure (DBP,-1.64mmHg, 95% CI:-3.28 to-0.01, P=0.049), and fasting blood glucose (FBG;-4.23mg/dl, 95% CI:-8.29 to-0.17, P=0.041) whereas changes in triglycerides (TG; 1.73mg/dl, 95% CI:-7.25 to 10.70, P=0.706), high-density lipoprotein cholesterol (HDL-C; 1.54mg/dl, 95% CI:-2.40 to 5.48, P=0.443), and body mass index (BMI;-0.23kg/m2, 95% CI:-0.97 to 0.51, P=0.545) was not statistically significant. Subgroup analyses based on intervention duration and Chlorella doses revealed that administration of Chlorella for 8 weeks or higher and doses higher than 4g/day significantly reduced TC, LDL-C, SBP, and DBP levels in the participants. Moreover, Chlorella supplementation significantly reduced TC and LDL-C levels in unhealthy individuals, and also reduced SBP and DBP in hypertensive ones. The results indicated that Chlorella supplementation improved levels of TC, LDL-C, SBP, DBP, and FBG but the changes in TG, HDL-C, and BMI were not satisfactory. More precise RCTs on subjects with different health status is recommended to clarify the effect of Chlorella supplementation on cardiovascular risk factors.

Comparative outcome of PFNA, Gamma nails, PCCP, Medoff plate, LISS and dynamic hip screws for fixation in elderly trochanteric fractures: a systematic review and network meta-analysis of randomized controlled trials.

The ideal implant for the treatment of an unstable intertrochanteric femoral fracture is still a matter of discussion. The aim of this systematic review is to conduct a network meta-analysis of randomized controlled trials (RCTs) comparing clinical outcomes between dynamic hip screws (DHS), Medoff sliding plating, percutaneous compression plating (PCCP), proximal femoral nails (PFN), Gamma nails and less invasive stabilization system fixation in femoral trochanteric fractures in the elderly. These clinical outcomes consist of total intra-operative time, intra-operative fluoroscopy time, intra-operative blood loss, blood component transfusion, length of hospital stay, postoperative general complications, wound complications, late complications and reoperation rates. This systematic review was conducted using PubMed and Scopus search engines for RCTs comparing clinical outcomes between treatments from inception to February 22, 2015. Thirty-six of 785 studies identified were eligible. Compared to the other implants, PCCP showed the lowest total operative time and units of blood transfusion with an unstandardized mean difference (UMD) of 29.27min (95% CI 5.24, 53.50) and 0.89 units (95% CI 0.52, 1.25). The lowest incidence of general complications, wound complications and late complications of PCCP was 0.09 (95% CI 0.04, 0.18), 0.01 (95% CI 0.01, 0.04) and 0.05 (95% CI 0.02, 0.11), respectively, when compared to others. The lowest fluoroscopic time was with DHS with an UMD of 0.24min (95% CI 0.16, 0.32), whereas the lowest blood loss and shortest hospital stay were with PFN with an UMD of 233.61ml of blood loss (95% CI 153.17, 314.04) and 7.23days of hospital stay (95% CI 7.15, 7.31) when compared to all other fixation methods. Reoperation rates of all implants had no statistically significant difference. The network meta-analysis suggested that fixation with PCCP significantly shortens operative time and decreases the units of blood transfusion required, while also lowering risks of general complications, wound complications and late complications when compared to fixation. Use of PFN showed the least intra-operative blood loss and shortest hospital stay. Multiple active treatment comparisons indicate that PCCP fixation in trochanteric fractures in the elderly is the treatment of choice in terms of intra-operative outcomes and postoperative complications.

Comparative Outcomes of Cortical Screw Trajectory Fixation and Pedicle Screw Fixation in Lumbar Spinal Fusion: Systematic Review and Meta-analysis.

We conducted a systematic review and meta-analysis to compare the postoperative outcomes of cortical screw and pedicle screw (PS) fixation techniques for posterior lumbar interbody fusion (PLIF). We searched all comparative studies that compared postoperative outcomes of cortical screw and PS fixation techniques for lumbar spinal fusions from the PubMed and Scopus databases up to 2 October2016. Eight of 1147 studies (N= 466 patients) were eligible: 5 back pain Visual Analog Scale (VAS); 4 leg pain VAS; 3 Oswestry Disability Index; 2 Japanese Orthopaedic Association scale; 5 intraoperative complications (dural tear and misplacement); 6 postoperative complications (hematoma, infection, adjacent segment disease and fracture); and 4 fusion rate studies were included. The unstandardized mean difference of back and leg pain VAS and Oswestry Disability Index of cortical bone trajectory (CBT) screw fixation was-0.14 (95% confidence interval [CI]:-2.46, 2.19),-0.46 (95% CI:-1.21, 0.29), and-1.64 (95% CI:-4.17, 0.89) scores lower than PS fixation for PLIF, but without statistical significance. Whereas PLIF with CBT screw fixation was insignificant higher Japanese Orthopaedic Association score of 0.87 (95% CI:-0.06, 1.81) when compared with PS fixation. CBT had a statistically significantly lower chance of postoperative complications by 0.49 (95% CI: 0.25, 0.95) when compared with PS fixation technique. However, CBT had no insignificant lower chance of intraoperative complication by 0.82 (95% CI: 0.28, 2.41) when compared with the PS technique. PLIF with CBT screw fixation had postoperative back and leg pain, disabilities, and function score.

Alar width changes due to surgically-assisted rapid palatal expansion: A meta-analysis.

A major objective of orthognatic surgery is the aesthetic outcome. Treatments only correcting for dentoskeletal deformities are not sufficient for optimal facial results because undesirable soft tissue changes may accompany skeletal manipulations. The primary objective of this study was to investigate alar base width (ABW) changes a minimum of 6 months following surgically-assisted rapid palatal expansion (SARPE). The following electronic databases and citation indices were searched: PubMed, Cochrane Library, Scopus, Web of Science, Embase, and Virtual Health Library. The search included articles published until September 2015 without language restriction. The intervention was SARPE with maxillary vestibular incision from first molar to contralateral first molar, a modified LeFort I osteotomy with or without pterygomaxillary disjunction, and a V-Y closure. The primary outcome was the unstandardized mean difference between pre and postoperative ABW. A random effects meta-analysis was performed to combine study results, and included studies that were assessed for statistical heterogeneity using a Chi-square test for independence. The results of this meta-analysis (N = 41) showed a significant + 1.74 mm, 95% CI [0.14, 3.34] ABW increase in patients submitted to SARPE. There was no statistical heterogeneity among included studies (χ2 = 0.03; df = 2; P = 0.98). ABW increases were observed despite including cinched patients in the analysis. None of the three included studies were completely free of bias. The most prominent flaws were measurement bias, limited sample size, and patient recruitment.

Comparison of surgical outcomes between fixation with hook plate and loop suspensory fixation for acute unstable acromioclavicular joint dislocation: a systematic review and meta-analysis.

Treatment of acute (≤4weeks) high-grade acromioclavicular (AC) joint separation (types III-VI) is still controversial. Currently, the two modern techniques that are widely used include hook plate fixation and coracoclavicular (CC) ligament fixation using a suspensory loop device (tightrope, synthetic ligament or absorbable polydioxansulfate sling). These techniques are both reported to have superior clinical outcomes. This systematic review and meta-analysis aimed to assess and compare clinical outcomes of hook plate fixation versus fixation of the CC ligament using a loop suspensory fixation (LSF) device for the treatment of AC joint injury. These clinical outcomes consist of the Constant-Murley score (CMS), pain visual analog score (VAS) and postoperative complications. Relevant comparative studies were identified from MEDLINE and Scopus from inception to October 5, 2015. Five of 571 studies were eligible; 5, 3, 3, and 5 studies were included in the pooling of CMS, pain VAS, surgical time and postoperative complications, respectively. The unstandardized mean difference (UMD) of the CMS for LSF was 4.43 [95% confidence interval (CI) 0.73, 8.14], which was statistically significantly higher than the CMS in hook plate fixation. For VAS, the UMD was 0.02 points (95% CI -3.54, 3.73) higher than LSF but without statistical significance. The surgical time of LSF was 16.21min (95% CI 6.27, 26.15) statistically significantly higher than hook plate fixation. LSF had a lower chance of postoperative complications by 0.62 units (95% CI 0.30, 1.32) when compared to hook plate fixation, but this also was not statistically significant. In acute high-grade AC joint injuries, loop suspensory fixation had higher postoperative functional CMS and mean surgical time when compared to hook plate fixation. However, for postoperative VAS and complication rates, there were no statistically significant differences between groups.

Effect of exercise training on sleep apnea: A systematic review and meta-analysis

IntroductionObstructive sleep apnea (OSA) is difficult to manage for those who are intolerant or noncompliant with standard facial mask treatment options. Current treatment options do not address the underlying cause of OSA. Exercise as a treatment option has been found to improve OSA indices. Study objectivesTo assess the efficacy of exercise on apnea/hypopnea index (AHI) in adult patients with OSA via a systematic review and meta-analysis. Additional objectives included evaluation of other indices of OSA and well-being in patients after completing an exercise regimen. Measurements and resultsWeb of Science, MEDLINE, CINAHL, and Cochrane Central Register of Controlled Trials were searched based on a priori criteria of all studies evaluating the effect of an exercise program on various sleep apnea indices. Both PRISMA statement and MOOSE consensus statement were adhered to. Eight Articles (182 participants) were included: a meta-analysis using a random effects model showed, a decrease in AHI (unstandardized mean difference [USMD], −0.536, 95% confidence interval [CI], −0.865 to −0.206, I2, 20%), reduced Epworth sleepiness scale (ESS) (USMD, −1.246, 95% CI, −2.397 to −0.0953, I2, 0%), and lower body mass index (BMI) (USMD, −0.0473, 95% CI, −0.0375 to 0.280, I2, 0%), in patients receiving exercise as treatment. Relative risks (RR) and odds ratios (OR) showed decreases in AHI (OR: 72.33, 95% CI, 27.906 to 187.491, RR: 7.294, 95% CI, 4.072 to 13.065) in patients receiving exercise as treatment. ConclusionAmong adult patients with OSA, exercise as the sole intervention was associated with improved clinical outcomes.

Effects of vitamin D on serum lipid profile in patients with type 2 diabetes: A meta-analysis of randomized controlled trials

The effect of vitamin D on lipid profile in type 2 diabetic patients is controversial. This meta-analysis aimed to assess the effect of vitamin D on serum total cholesterol (TC), triglycerides (TG), low-density lipoproteins (LDL), and high-density lipoproteins (HDL) of these patients to elucidate the subject. Seven databases were searched and randomized controlled trials (RCTs) assessed the effect of vitamin D on lipid profile published until November 2015 were identified. Un-standardized mean difference and its corresponding 95% confidence interval (CI) was calculated from the effect sizes by using random effects model. We found 2220 articles in our systematic search, after exclusion of un-related studies we enrolled 17 studies comparing intervention group (received vitamin D) with control group (received placebo) in the meta-analysis. Vitamin D significantly reduced serum TC (-3.74mg/dl, 95% CI:-7.13 to-0.34, P=0.031), but serum TG did not show significant reduction (-4.90mg/dl, 95% CI:-15.11-5.31, P=0.347). Results confirmed the significant lowering effect of vitamin D on LDL in patients with T2D (-2.55mg/dl, 95% CI:-4.83 to-0.26, P=0.029), but change in serum HDL was negligible (-0.72mg/dl, 95% CI:-1.27 to-0.17, P=0.010). Subgroup analyses showed that the baseline serum 25-hydroxy vitamin D of patients, vitamin D dosage, intervention duration, and the method of vitamin D application influence the effect of vitamin D on lipid markers. This study demonstrated that vitamin D improved serum levels of TC, TG, and LDL in patients with T2D but changes of serum HDL was not satisfactory.

Efficacy of additional psychosocial intervention in reducing low birth weight and preterm birth in teenage pregnancy: A systematic review and meta-analysis

This systematic review aimed to assess the efficacy of psychosocial interventions in reducing risk of low birth weight (LBW) and preterm birth (PTB) in teenage pregnancy. Relevant studies were identified from Medline, Scopus, CINAHL, and CENTRAL databases. Randomized controlled trials investigating effect of psychosocial interventions on risk of LBW and PTB, compared to routine antenatal care (ANC) were eligible. Relative risks (RR) of LBW and PTB were pooled using inverse variance method. Mean differences of birth weight (BW) between intervention and control groups were pooled using unstandardized mean difference (USMD). Five studies were included in the review. Compared with routine ANC, psychosocial interventions significantly reduced risk of LBW by 40% (95%CI: 8%,62%) but not for PTB (pooled RR = 0.67, 95%CI: 0.42,1.05). Mean BW of the intervention group was significantly higher than that of the control group with USMD of 200.63 g (95% CI: 21.02, 380.25). Results of our study suggest that psychosocial interventions significantly reduced risk of LBW in teenage pregnancy.

The effect of supplementation with alkaline potassium salts on bone metabolism: a meta-analysis

The role of acid-base metabolism in bone health is controversial. In this meta-analysis, potassium bicarbonate and potassium citrate lowered urinary calcium and acid excretion and reduced the excretion of the bone resorption marker NTX. These salts may thus be beneficial to bone health by conserving bone mineral. The role of acid-base homeostasis as a determinant of bone health and the contribution of supplemental alkali in promoting skeletal integrity remain a subject of debate. The objective of this study was, therefore, to conduct a meta-analysis to assess the effects of supplemental potassium bicarbonate (KHCO3) and potassium citrate (KCitr) on urinary calcium and acid excretion, markers of bone turnover and bone mineral density (BMD) and to compare their effects with that of potassium chloride (KCl). A total of 14 studies of the effect of alkaline potassium salts on calcium metabolism and bone health, identified by a systematic literature search, were analysed with Review Manager (Version 5; The Cochrane Collaboration) using a random-effects model. Authors were contacted to provide missing data as required. Results are presented as the standardised (SMD) or unstandardized mean difference (MD) (95 % confidence intervals). Urinary calcium excretion was lowered by intervention with both KHCO3 (P = 0.04) and KCitr (P = 0.01), as was net acid excretion (NAE) (P = 0.002 for KHCO3 and P = 0.0008 for KCitr). Both salts significantly lowered the bone resorption marker NTX (P < 0.00001). There was no effect on bone formation markers or BMD. KHCO3 and KCitr lowered calcium excretion to a greater extent than did KCl. This meta-analysis confirms that supplementation with alkaline potassium salts leads to significant reduction in renal calcium excretion and acid excretion, compatible with the concept of increased buffering of hydrogen ions by raised circulating bicarbonate. The observed reduction in bone resorption indicates a potential benefit to bone health.

Patellofemoral resurfacing and patellar denervation in primary total knee arthroplasty

To conduct a systematic review and network meta-analysis of randomized controlled trials (RCTs) with the aim of comparing relevant clinical outcomes between patellar denervation, resurfacing and non-resurfacing. A database search was performed using PubMed and Scopus search engines. RCTs or quasi-experimental designs comparing clinical outcomes between treatments by a search of articles dated from inception to October 23, 2012. Unstandardized mean difference (UMD) and random effects methods were applied for pooling continuous and dichotomous outcomes, respectively. A longitudinal mixed regression model was used for network meta-analysis to indirectly compare treatment effects. Eighteen of 315 studies identified were eligible. Compared with patellar non-resurfacing, patellar denervation had a UMD that displayed a significant improvement in symptoms with values in pain visual analog score (VAS) and Knee Society Score (KSS) of -0.6 [95% confidence interval (CI) -1.13, -0.25] and 2.55 (95% CI 0.43, 4.68), respectively. The UMD in VAS, KSS, and Knee Function Score (KFS) in patellar resurfacing showed no significant improvement in symptoms when compared to non-resurfacing. Patients who underwent surgery with patellar resurfacing had a lower reoperation rates with pooled relative risks (RRs) of 0.69 (95% CI 0.50, 0.94) when compared to non-resurfacing. The network meta-analysis suggested a benefit of borderline significance for patellar denervation with a pooled RR of 0.63 (95% CI 0.38, 1.03), showing that there is a lower chance of anterior knee pain when compared to non-resurfacing. Patellar resurfacing also displays a significantly lower chance of reoperation with a pooled RR of 0.68 (95% CI 0.50, 0.92) when compared to non-resurfacing. Multiple active treatment comparisons indicated that patellar denervation resulted in greater improvement in KFS than patellar resurfacing. This review suggests that either patellar denervation or patellar resurfacing may be selected for the management of the patellofemoral component in total knee replacement. Patellar denervation may help improve postoperative knee function, but does not improve pain when compared to patellar resurfacing.

Mean platelet volume and coronary artery disease: a systematic review and meta-analysis

BackgroundPlatelets with high hemostatic activity play an important role in the pathophysiology of coronary artery disease(CAD) and mean platelet volume(MPV) has been proposed as an indicator of platelet reactivity. Thus, MPV may emerge as a potential marker of CAD risk. The aim of this study was to conduct a systematic review and meta-analysis comparing mean difference in MPV between patients with CAD and controls and pooling the odds ratio of CAD in those with high versus low MPV. MethodsMedline and Scopus databases were searched up to 12 March 2013. All observational studies that considered MPV as a study's factor and measured CAD as an outcome were included. Two reviewers independently selected the studies and extracted the data. ResultsForty studies were included in this meta-analysis. The MPV was significantly larger in patients with CAD than controls with the unstandardized mean difference of 0.70fL (95% CI: 0.55, 0.85). The unstandardized mean difference of MPV in patients with acute coronary event and in patients with chronic stable angina was 0.84fL (95% CI: 0.63, 1.04) and 0.46fL (95% CI: 0.11, 0.81) respectively. Patients with larger MPV (≥7.3fL) also had a greater odds of having CAD than patients with smaller MPV with a pooled odds ratio of 2.28 (95% CI: 1.46, 3.58). ConclusionLarger MPV was associated with CAD. Thus, it might be helpful in risk stratification, or improvement of risk prediction if combining it with other risk factors in risk prediction models.

Development and Monte Carlo Study of a Procedure for Correcting the Standardized Mean Difference for Measurement Error in the Independent Variable.

The standardized mean difference (SMD) is perhaps the most important meta-analytic effect size. It is typically used to represent the difference between treatment and control population means in treatment efficacy research. It is also used to represent differences between populations with different characteristics, such as persons who are depressed and those who are not. Measurement error in the independent variable (IV) attenuates SMDs. In this article, we derive a formula for the SMD that explicitly represents accuracy of classification of persons into populations on the basis of scores on an IV. We suggest an alternate version of the SMD less vulnerable to measurement error in the IV. We derive a novel approach to correcting the SMD for measurement error in the IV and show how this method can also be used to reliability correct the unstandardized mean difference. We compare this reliability correction approach with one suggested by Hunter and Schmidt in a series of Monte Carlo simulations. Finally, we consider how the proposed reliability correction method can be used in meta-analysis and suggest future directions for both research and further theoretical development of the proposed reliability correction method.

A cross-sectional study of health-related quality of life deficits in individuals with comorbid diabetes and cancer.

BackgroundNumerous studies have identified a reduced health related quality of life (HRQL) in patients that have either diabetes or cancer. We assessed the HRQL burden in patients with these comorbid conditions, postulating that they would have even greater HRQL deficits.MethodsData from the Public Use File of the Canadian Community Health Survey (PUF CCHS) Cycle 1.1 (September 2000–November 2001) were used for this analysis. The total sample size of the CCHS PUF is 130,880 individuals. We used the Health Utilities Index Mark 3 (HUI3) to assess HRQL in patients with: 1) comorbid diabetes and cancer, 2) diabetes alone, 3) cancer alone, and 4) no diabetes or cancer. Analysis of covariance was used to compare the mean overall HUI3 score, controlling for age, sex, marital status, body mass index (BMI), physical activity level, smoking status, education level, depression status, and other chronic conditions.ResultsWe identified 113,587 individuals (87%) with complete data for the analysis. The comorbid diabetes and cancer group were older and a larger proportion reported being obese, inactive, having less than a secondary education and more chronic conditions when compared to the other three cohorts (p < 0.0001). However, the diabetes and cancer cohort was less likely to be depressed (p < 0.0001). Overall HUI3 scores were significantly lower for the diabetes and cancer group (unadjusted mean (SD): 0.67 (0.30)), compared to diabetes (0.78 (0.27)), cancer (0.78 (0.25)), and the reference group (0.89 (0.18)) (p < 0.0001). After adjusting for covariates, the comorbid diabetes and cancer group continued to have significantly lower overall HUI3 scores than the reference group (unstandardized mean difference: -0.11, 95% CI: -0.13 to -.0.09) (p < 0.0001).ConclusionIndividuals with diabetes and cancer had a clinically important and significantly lower HRQL than those with either condition alone. A better understanding of the relationship between diabetes and cancer, and their associated comorbidities, complications, and HRQL deficits may have important implications for prevention and management strategies.