This article was previously published with an error. There is an issue with labelling for socio-economic grade. The item for this variable asks participants to state the profession of the highest earner in the household. We categorised participants into two groups: highest earner works in a manual occupation, and highest earner does not work in a manual occupation. The levels of these variables are referred to in some of our project's manuscripts as 'socio-economic grade C1DE' and 'socio-economic grade ABC1', respectively. These would be better denoted as 'highest earner in household works in a manual occupation' and 'highest earner in household does not work in a manual occupation'. This labelling error came about through multiple iterations of documents.
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