Abstract:The content validity ratio originally proposed by Lawshe is widely used to quantify content validity and yet methods used to calculate the original critical values were never reported. Methods for original calculation of critical values are suggested along with tables of exact binomial probabilities.

BackgroundReducing emergency admissions to hospital has been a cornerstone of healthcare policy. Little evidence exists to show that systematic interventions across a population have achieved this aim. The authors report the impact of a complex intervention over a 44-month period in Frome, Somerset, on unplanned admissions to hospital.AimTo evaluate a population health complex intervention of an enhanced model of primary care and compassionate communities on population health improvement and reduction of emergency admissions to hospital.Design and settingA cohort retrospective study of a complex intervention on all emergency admissions in Frome Medical Practice, Somerset, compared with the remainder of Somerset, from April 2013 to December 2017.MethodPatients were identified using broad criteria, including anyone giving cause for concern. Patient-centred goal setting and care planning combined with a compassionate community social approach was implemented broadly across the population of Frome.ResultsThere was a progressive reduction, by 7.9 cases per quarter (95% confidence interval [CI] = 2.8 to 13.1, P = 0.006), in unplanned hospital admissions across the whole population of Frome during the study period from April 2013 to December 2017, a decrease of 14.0%. At the same time, there was a 28.5% increase in admissions per quarter within Somerset, with a rise in the number of unplanned admissions of 236 per quarter (95% CI = 152 to 320, P<0.001).ConclusionThe complex intervention in Frome was associated with highly significant reductions in unplanned admissions to hospital, with a decrease in healthcare costs across the whole population of Frome.

An optimized horizontal-vertical visual illusion led to significant increases in foot clearance in older adults when ascending a staircase, but the effects did not destabilize their postural stability. Inclusion of the horizontal-vertical illusion on raised surfaces (e.g., curbs) or the bottom and top stairs of staircases could improve stair ascent safety in older adults.

PurposeTo determine whether dizziness and falls rates change due to routine cataract surgery and to determine the influence of spectacle type and refractive factors.MethodsSelf‐reported dizziness and falls were determined in 287 patients (mean age of 76.5 ± 6.3 years, 55% females) before and after routine cataract surgery for the first (81, 28%), second (109, 38%) and both eyes (97, 34%). Dizziness was determined using the short‐form of the Dizziness Handicap Inventory. Six‐month falls rates were determined using self‐reported retrospective data.ResultsThe number of patients with dizziness reduced significantly after cataract surgery (52% vs 38%; χ2 = 19.14, p < 0.001), but the reduction in the number of patients who fell in the 6‐months post surgery was not significant (23% vs 20%; χ2 = 0.87, p = 0.35). Dizziness improved after first eye surgery (49% vs 33%, p = 0.01) and surgery on both eyes (58% vs 35%, p < 0.001), but not after second eye surgery (52% vs 45%, p = 0.68). Multivariate logistic regression analyses found significant links between post‐operative falls and change in spectacle type (increased risk if switched into multifocal spectacles). Post‐operative dizziness was associated with changes in best eye visual acuity and changes in oblique astigmatic correction.ConclusionsDizziness is significantly reduced by first (or both) eye cataract surgery and this is linked with improvements in best eye visual acuity, although changes in oblique astigmatic correction increased dizziness. The lack of improvement in falls rate may be associated with switching into multifocal spectacle wear after surgery.

AimsLevels of false positive referral to ophthalmology departments can be high. This study aimed to evaluate commonality between false positive referrals in order to find the factors which may influence referral accuracy.MethodsIn 2007/08, a sample of 431 new Ophthalmology referrals from the catchment area of Bradford Royal Infirmary were retrospectively analysed.ResultsThe proportion of false positive referrals generated by optometrists decreases with experience at a rate of 6.2% per year since registration (p < 0.0001). Community services which involved further investigation done by the optometrist before directly referring to the hospital were 2.7 times less likely to refer false positively than other referral formats (p = 0.007). Male optometrists were about half as likely to generate a false positive referral than females (OR = 0.51, p = 0.008) and as multiple/corporate practices in the Bradford area employ less experienced and more female staff, independent practices generate about half the number of false positive referrals (OR = 0.52, p = 0.005).ConclusionsClinician experience has the greatest effect on referral accuracy although there is also a significant effect of gender with women tending to refer more false positives. This may be due to a different approach to patient care and possibly a greater sensitivity to litigation. The improved accuracy of community services (which often refer directly after further investigation) supports further growth of these schemes.