From The Spectator:

While some studies claim to have quantified a beneficial effect from lockdown measures during the first wave of Covid-19, a study at Stanford University questions this…. Dr Eran Bendavid and Professor John Ioannidis studied the imposition of ‘non-pharmaceutical interventions’ (NPIs) in ten countries and have reached the conclusion that while less-restrictive NPIs (which include social distancing and appeals to the public to reduce their social activities) had a clear effect, more-restrictive NPIs (which include business closures and stay at home orders) produced no clear additional benefits….Their paper, published in the European Journal of Clinical Observation, argues that previous studies on NPIs tended to assume that all beneficial effects were the result of the last measures that happen to have been imposed (i.e. the most severe measures), or failed to take into account the dynamic nature of an epidemic curve, assuming that the epidemic would have continued growing at the same rate it was rising before the measures were imposed…. Their conclusion? That all the apparent benefits were derived from less-restrictive NPIs and from changes in public behaviour following the imposition of the lighter restrictions. Ordering businesses to close and telling people to stay at home did not appear to reduce rates of infection further. 

Measuring the impact of stay-at-home lockdown measures 13 Jan 2021