Prospective Analytical Cohort Study Research Articles

Motor control and strength as predictors of hamstring injury in elite players of Australian football

Objectives. To investigate motor control as a possible contributing factor in hamstring injuries using a test movement similar to the injury-critical phase during running. Leg swing movement discrimination (MD), thigh muscle strength as tested by Cybex isokinetic dynamometry and previous hamstring injury history were all assessed to determine any association with subsequent hamstring injury. Design. Prospective and retrospective observational and analytical cohort study. Setting. A professional football club and a university laboratory. Participants. Twenty elite level players of Australian football. Results. In the 2 years prior to testing, 7 subjects had sustained a hamstring injury. At the time of testing, there were no significant differences between subjects never injured and those previously injured. In the two years following testing, 6 players sustained a hamstring injury. Mean MD score and concentric hamstring-to-quadriceps strength ratio of subsequently injured subjects were significantly worse than those uninjured ( p<0.05). Optimum cutoffs on these measures were determined. Conclusion. Both a lower MD ability score for the backward swinging leg and an imbalance of thigh muscle strength were predictive of hamstring injury.

The Toronto Tri-Hospital Gestational Diabetes Project

Sermer, Mathew; Naylor, C. David; Farine, Dan; Kenshole, Anne B.; Ritchie, J. W. K.; Gare, Douglas J.; Cohen, Howard R.; McArthur, Karen; Holzapfel, Stephen; Biringer, Anne Author Information

Impact of increasing carbohydrate intolerance on maternal-fetal outcomes in 3637 women without gestational diabetes: The Toronto tri-hospital gestational diabetes project

OBJECTIVE: Our purpose was to assess maternal-fetal outcomes in patients with increasing carbohydrate intolerance not meeting the current criteria for the diagnosis of gestational diabetes. STUDY DESIGN: We conducted a prospective analytic cohort study in which nondiabetic women aged ≥24 years, receiving prenatal care in three Toronto teaching hospitals, were eligible for enrollment. A glucose challenge test and an oral glucose tolerance test were administered at 26 and 28 weeks' gestation, respectively; risk factors for unfavorable maternal-fetal outcomes were recorded. Caregivers and patients were blinded to glucose values except when test results met the current criteria for gestational diabetes. RESULTS: Of 4274 patients screened, 3836 (90%) continued to the diagnostic oral glucose tolerance test. The study cohort was formed by the 3637 (95%) patients without gestational diabetes, carrying singleton fetuses. Increasing carbohydrate intolerance in women without overt gestational diabetes was associated with a significantly increased incidence of cesarean sections, preeclampsia, macrosomia, and need for phototherapy, as well as an increased length of maternal and neonatal hospital stay. Multivariate analysis showed that increasing carbohydrate intolerance is an independent predictor for various unfavorable outcomes. CONCLUSION: Increasing maternal carbohydrate intolerance in pregnant women without gestational diabetes is associated with a graded increase in adverse maternal-fetal outcomes.

A Comparison of Outcomes Between Joint and Physician‐Only Obstetric Practices

Since 1981, the cesarean birth rate of a joint practice has been consistently lower than that of physician-only practices at a private community hospital in Yolo County, California. This study sought to determine whether differences in perinatal outcomes were influenced by women's use of a joint versus a physician-only practice or were associated with parity, maternal age, or newborn birthweight. Data from the hospital's 1634 consecutive singleton births in 1990 were examined, using a prospective concurrent analytic cohort study design. Chi square statistics and stepwise logistic regressions were used for data analysis. The joint practice had a significantly lower rate of total cesarean births (9.3%) compared with the physician-only practices (17.7%); the frequencies of severe lacerations were 1.0 percent and 6.4 percent, respectively. No significant differences were found in parity, birthweight, or newborn outcomes in the two types of practice. Type of practice was the major determinant of cesarean birth (p < 0.0001). All variables studied, including type of practice, were significant determinants of primary cesarean birth. Parity and practice type were significant determinants of third- and fourth-degree lacerations (p < 0.0001). The type of practice from which women receive care is significantly associated with both method of birth and possibility of severe perineal trauma.

Impact of time since last meal on the gestational glucose challenge test: The Toronto Tri-Hospital Gestational Diabetes Project

The purpose of the study was to evaluate the impact of time since the last meal on the glucose challenge test and to find cut points that are most likely to predict the outcome of the oral glucose tolerance test in patients screened for gestational diabetes. This prospective analytic cohort study was carried out at the University of Toronto Perinatal Complex. A 50 gm glucose load was given at 26 weeks' gestation and the time since previous meal ingestion was recorded. At 28 weeks' gestation a 100 gm oral glucose tolerance test was administered. A total of 4274 eligible patients were screened. Time since the last meal had a marked effect on mean plasma glucose. Receiver-operator characteristic curve analysis with National Diabetes Data Group criteria to interpret the oral glucose tolerance allowed the selection of the most efficient cut points for the glucose challenge test on the basis of time since the last meal. These cut points were 8.2, 7.9, and 8.3 mmol/L for elapsed postprandial times of < 2, 2 to 3, and > 3 hours, respectively. With this change from the current threshold of 7.8 mmol/L the number of patients with a positive screening test dropped from 18.5% to 13.7%. There was an increase in positive predictive value from 14.4% to 18.7%. The rate of patient misclassification fell from 18.0% to 13.1%. We suggest that screening strategies for detection of gestational diabetes be reconsidered, to account for the impact of variable postprandial status on the test results.