2 In a study conducted in the northwest of England, 103 dental practice patients diagnosed with a failed restoration underwent either a replacement or a repair (Javidi, Tickle, and Aggarwal 2015). The fi ndings regarding the time taken by the dentist to complete the intervention were as follows:

Repair group

(n = 37)

Replacement group (n = 66)

P- value Mean time taken (mins) 21.65 (SD 8.02) 25.15 (SD 8.55) P = 0.044

(i) State an appropriate null hypothesis about the time taken to perform the procedure for the two groups.

(ii) Explain the statement “P = 0.044”. What further information about the difference between the mean procedure times would have improved the presentation of the results?