A School of Continuous Improvement paper pilots a four-level capability maturity model for kerbside sorting, self-attested by 2,140 households, and finds contamination rising fastest among the households whose top score ended the audits that would have caught it.
A four-level kerbside maturity model finds contamination climbing fastest among the households its top score exempted from audit
Four named levels now decide how closely anyone checks a household’s bin. A new paper from the School of Continuous Improvement reports a waste-services contractor’s pilot of a Kerbside Capability Maturity Model, self-attested annually by 2,140 households and checked, for a smaller blind subsample, by an independent assessor. The households who first attested the model’s top tier are the same households whose contamination rate has since climbed fastest, over the two years an audit exemption kept anyone from looking again.
A maturity model is supposed to describe an institution once and then get out of the way. This one kept describing bin night for two years after the contractor had already decided not to look again.
— Dr Sten Okwuosa, Senior Research Fellow and Convenor, Impact Pathway Atlas, School of Continuous Improvement
The study, led by Dr Okwuosa with Dr Thandiwe Solberg and Dr Joost Nwosu, attested 2,140 households against the model’s published rubric across three collection years and cross-checked a stratified subsample of 312 against the same criteria, blind to each household’s own score. “A Level Three attestation was supposed to be the beginning of a standard being kept,” said Dr Nwosu, “not the end of anyone checking whether it still was.”
The School reads the finding as sitting inside its wider account of what a credential is left measuring once the checking that built it stops. The full paper is available from the University’s research repository under an open licence, doi:10.5555/slop.3cs0pf.