Intro to Social Psychology

I need an explanation for this Psychology question to help me study.

Soon after the World Health Organization declared a pandemic on March 11, 2020, Canadian jurisdictions implemented social and physical distancing measures as recommended by federal and provincial public health authorities. Among the public health mandates was the advice to stay home as much as possible. The results of a recent psychology survey indicated that young Canadian adults who stayed indoors and completely avoided contact with other people used 20% more cannabis than those who did not self-isolate.

Can we conclude from these results that self-isolation caused increased cannabis use? In a paragraph or two, explain why or why not.