Kerry Ritchie

How to Achieve Accurate Peer Assessment for High Value Written Assignments in a Senior Undergraduate Course.

The psychometric measures of accuracy, reliability and validity of peer assessment are critical qualities for its use as a supplement to instructor grading. In this study, we seek to determine which factors related to peer review are the most influential on these psychometric measures, with a primary focus on the accuracy of peer assessment or how closely peer-given grades match those of an instructor. We examine and rank the correlations of accuracy, reliability and validity with 17 quantitative and qualitative variables for three senior undergraduate courses that used peer assessment on high value written assignments. Based on these analyses, we altered the single most significant variable of one of the courses. We demonstrate that the number of reviews completed per reviewer has the greatest influence on the accuracy of peer assessment out of all the factors analysed. Our calculations suggest that six reviews must be completed per reviewer to achieve peer assessment that is no different from the grading of an instructor. Effective training, previous experience and strong academic abilities in the reviewers may reduce this number.

Exercise training is an effective alternative to estrogen supplementation for improving glucose homeostasis in ovariectomized rats

The irreversible loss of estrogen (specifically 17‐β‐estradiol; E2) compromises whole‐body glucose tolerance in women. Hormone replacement therapy (HRT) is frequently prescribed to treat estrogen deficiency, but has several deleterious side effects. Exercise has been proposed as an HRT substitute, however, their relative abilities to treat glucose intolerance are unknown. Thirty ovariectomized (OVX) and 20 SHAM (control) rats underwent glucose tolerance tests (GTT) 10 weeks post surgery. Area under the curve (AUC) for OVX rats was 60% greater than SHAM controls (P = 0.0005). Rats were then randomly assigned to the following treatment groups: SHAM sedentary (sed) or exercise (ex; 60 min, 5×/weeks), OVX sed, ex, or E2 (28 μg/kg bw/day) for 4 weeks. OVX ex rats experienced a ~45% improvement in AUC relative to OVX sed rats, whereas OVX E2 underwent a partial reduction (17%; P = 0.08). Maximal insulin‐stimulated glucose uptake in soleus and EDL was not impaired in OVX rats, or augmented with exercise or E2. Akt phosphorylation did not differ in soleus, EDL, or liver of any group. However, OVX ex and OVX E2 experienced greater increases in p‐Akt Ser473 in VAT and SQ tissues compared with SHAM and OVX sed groups. Mitochondrial markers CS, COXIV, and core1 were increased in soleus posttraining in OVX ex rats. The content of COXIV was reduced by 52% and 61% in SQ of OVX sed and E2 rats, compared to SHAM controls, but fully restored in OVX ex rats. In summary, exercise restores glucose tolerance in OVX rats more effectively than E2. This is not reflected by alterations in muscle maximal insulin response, but increased insulin signaling in adipose depots may underlie whole‐body improvements.

Cheating after the test: who does it and how often?

Self-reports suggest >50% of university students cheat at some point in their academic career (Christensen Hughes JM, McCabe DL. Can J High Educ 36: 49-63, 2006), although objective values of academic misconduct (AM) are difficult to obtain. In a physiology-based department, we had a concern that students were altering written tests and resubmitting them for higher grades; thereby compromising the integrity of our primary assessment style. Therefore, we directly quantified the prevalence of AM on written tests in 11 courses across the department. Three thousand six hundred and twenty midterms were scanned, and any midterm submitted for regrading was compared with its original for evidence of AM. Student characteristics, test details, and course information were recorded. On a department level, results show that this form of AM was rare: prevalent on 2.2% of all tests written. However, of the tests submitted for regrading, 17.4% contained AM (range: 0-26%). The majority of AM was conducted by high-achieving students, (60% of offenders earned >80%), and there was a trend toward women being more likely to commit AM (P = 0.056). While our results objectively show that this type of AM is low, we highlight that large competitive courses face significantly higher prevalence, and high-achieving students may have gone underreported in previous literature. Vigilance should be employed by all faculty who accept tests for regrading.