Changes in primary care visits arising from the COVID-19 pandemic: an international comparative study by the International Consortium of Primary Care Big Data Researchers (INTRePID... by Tu, K, Sarkadi Kristiansson, R, Gronsbell, J, de Lusignan, S, Flottorp, S, Goh, LH, Hallinan, CM, Hoang, U, Kang, SY, Kim, YS, Li, Z, Ling, ZJ, Manski-Nankervis, J-A, Ng, APP, Pace, WD, Wensaas, K-A, Wong, WC, Stephenson, E