Chasing rainbows? Ofsted's quest for inter-inspector reliability

Ofsted has frequently defended the judgements made during inspections by claiming that inspection ratings are reliable, as shown by the results from the collection of studies the inspectorate has conducted. I outline the inspectorate's view of reliability and problematise the studies that it has carried out, noting that these provide insufficient evidence to support Ofsted's claims. I describe a recent study, which utilised an alternative approach to studying the reliability of inspection outcomes, by way of introducing a short discussion of why the inspectorate needs to develop a more productive view of reliability that reflects better the inherent variability of inspectors' decision-making and judgements.