What is the test for determining whether an employee is an employee under the Ontario Compensation Act?

'The question of whether a worker is an employee within the meaning of the Compensation Act * * * is referred to as a question of mixed law and fact to be proved like any other question. [Citations.] It is a question of fact upon which the judgment of the commission is conclusive where the facts are in dispute. It becomes a question of law only when but one inference can reasonably be drawn from the facts. Where two opposing inferences may be drawn from the evidence, and the inference accepted by the commission is reasonable, and is supported by evidence in the record, that inference must be sustained.' (Schaller v. Industrial Acc. Com., 11 Cal.2d 46, 51, 77 P.2d 836, 839.)