Report showing revenue by appointment

Calculating commissions for self employed practitioners is difficult if a patient has booked and paid online as the payment and invoice date differs from the date the actual appointment has taken place. If I run a closed invoice report for the week, it does not accurately the amount earnt in that week for that practitioner. Is it possible to look at having a report that shows revenue by appointment date as this would more accurately show the actual amount earnt each week/month etc?