Clinically and temporally specific diagnostic thresholds for plasma ACTH in the horse.

BACKGROUND: Pituitary pars intermedia dysfunction (PPID) is commonly investigated using plasma ACTH concentrations but problems exist with currently available diagnostic thresholds. OBJECTIVES: To derive temporally specific diagnostic thresholds for equine plasma ACTH concentration to be used alongside clinical judgement in each individual week of the year and appropriate for the degree of clinical suspicion in any given case. Furthermore, to apply these thresholds to compare the prevalence of high and low ACTH in two subgroups of animals with high and low clinical suspicion of PPID. STUDY DESIGN: A retrospective population study examining a large laboratory database of equine plasma ACTH concentrations using an indirect approach to calculate diagnostic thresholds. METHODS: Logs of plasma ACTH concentrations from 75 892 individual horses were examined using robust L2 estimation of mixtures of two normal distributions in categories of each week and month of the year. Thresholds dividing the two populations of high-ACTH and low-ACTH horses were then established at different levels of sensitivity and specificity and compared with clinical subgroups of horses divided based on reported clinical signs, as having high (n = 4036) or low (n = 3022) clinical suspicion of PPID. RESULTS: For most of the year there were small interweek differences in diagnostic thresholds. However, from mid-June to early-December diagnostic thresholds showed greater interweek variability, reaching a maximum in late September and early October. Grouping of high- and low-ACTH compared favourably with grouping based on clinical signs. MAIN LIMITATIONS: Given the multiple sources of diagnostic samples, pre-analytical data could not be fully verified. CONCLUSIONS: Diagnostic thresholds for equine plasma ACTH vary through the year. It is especially important to consider the temporally specific threshold between June and December. Different clinical thresholds can be used depending on the case circumstances and whether a false-positive or false-negative diagnosis is deemed least desirable.

Outcomes of usual chiropractic. The OUCH randomized controlled trial of adverse events.

STUDY DESIGN: Blinded parallel-group randomized controlled trial. OBJECTIVE: Establish the frequency and severity of adverse effects from short-term usual chiropractic treatment of the spine when compared with a sham treatment group. SUMMARY OF BACKGROUND DATA: Previous studies have demonstrated that adverse events occur during chiropractic treatment. However, as a result of design limitations in previous studies, particularly the lack of sham-controlled randomized trials, understanding of these adverse events and their relation with chiropractic treatment is suboptimal. METHODS: We conducted a trial to examine the occurrence of adverse events resulting from chiropractic treatment. It was conducted across 12 chiropractic clinics in Perth, Western Australia. The participants comprised 183 adults, aged 20 to 85 years, with spinal pain. Ninety-two participants received individualized care consistent with the chiropractors' usual treatment approach; 91 participants received a sham intervention. Each participant received 2 treatments. RESULTS: Completed adverse questionnaires were returned by 94.5% of the participants after appointment 1 and 91.3% after appointment 2. Thirty-three percent of the sham group and 42% of the usual care group reported at least 1 adverse event. Common adverse events were increased pain (sham 29%; usual care 36%), muscle stiffness (sham 29%; usual care 37%), and headache (sham 17%; usual care 9%). The relative risk (RR) was not significant for adverse event occurrence (RR = 1.24; 95% CI: 0.85-1.81), occurrence of severe adverse events (RR = 1.9; 95% CI: 0.98-3.99), adverse event onset (RR = 0.16; 95% CI: 0.02-1.34), or adverse event duration (RR = 1.13; 95% CI: 0.59-2.18). No serious adverse events were reported. CONCLUSION: A substantial proportion of adverse events after chiropractic treatment may result from natural history variation and nonspecific effects. LEVEL OF EVIDENCE: 2.

Outcomes of usual chiropractic, harm & efficacy, the ouch study: study protocol for a randomized controlled trial.

BACKGROUND: Previous studies have demonstrated that adverse events occur during chiropractic treatment. However, because of these studies design we do not know the frequency and extent of these events when compared to sham treatment. The principal aims of this study are to establish the frequency and severity of adverse effects from short term usual chiropractic treatment of the spine when compared to a sham treatment group. The secondary aim of this study is to establish the efficacy of usual short term chiropractic care for spinal pain when compared to a sham intervention. METHODS: One hundred and eighty participants will be randomly allocated to either usual chiropractic care or a sham intervention group. To be considered for inclusion the participants must have experienced non-specific spinal pain for at least one week. The study will be conducted at the clinics of registered chiropractors in Western Australia. Participants in each group will receive two treatments at intervals no less than one week. For the usual chiropractic care group, the selection of therapeutic techniques will be left to the chiropractors' discretion. For the sham intervention group, de-tuned ultrasound and de-tuned activator treatment will be applied by the chiropractors to the regions where spinal pain is experienced. Adverse events will be assessed two days after each appointment using a questionnaire developed for this study. The efficacy of short term chiropractic care for spinal pain will be examined at two week follow-up by assessing pain, physical function, minimum acceptable outcome, and satisfaction with care, with the use of the following outcome measures: Numerical Rating Scale, Functional Rating Index, Neck Disability Index, Minimum Acceptable Outcome Questionnaire, Oswestry Disability Index, and a global measure of treatment satisfaction. The statistician, outcome assessor, and participants will be blinded to treatment allocation. TRIAL REGISTRATION: Australia and New Zealand Clinical Trials Register (ANZCTR): ACTRN12611000542998.

The benefits and limitations of the sperm quality analyzer IIB in assessing porcine sperm motility.

The Sperm Quality Analyzer (SQA) IIB, a member of the SQA-II family of machines which uses the scatter of light by sperm as an indicator of sperm motility, was systematically evaluated as a means of analyzing objectively the motility of porcine epididymal sperm. The sperm motility (%) and the Sperm Motility Index (SMI) are calculated by the machine using pre-programmed algorithms designed for human sperm. The machine performed well and was able to detect changes in sperm motility under experimental conditions. However, two major limitations of this machine were identified, (i) the readings obtained were influenced by the concentration of the sperm suspension despite the actual sperm motility remaining constant, and (ii) the machine was unable to differentiate between progressive and non-progressive motility. It should therefore be recognized that (a) the sperm concentration must be kept constant in studies in vitro if differences between treatment groups are to be identified, and (b) the inability to separate progressive motility from that of total motility will restrict the usefulness of this and similar machines to studies monitoring changes in total motility alone.