The study will take the form of a prospective randomised clinical trial. The following assessment tools will be used
* The visual analogue scale (VAS) consists of a 100 mm horizontal line with the two end points labelled "no pain" and "worst pain ever". Patients are asked to mark on the line a point that corresponds to the level of pain intensity they feel. The score is obtained by measuring the distance (mm) from the left end of the line.
* The short-form McGill Pain Questionnaire (SF-MPQ) consists of 15 representative words from the sensory and affective categories of the standard McGill Pain Questionnaire. It also includes the present pain intensity and a VAS to provide overall indices of pain intensity. It has been shown to be sensitive to clinical changes brought about by various interventions, postoperative analgesic drugs (6).
* The Pain Catastrophising Score (PCS) is a 13 item instrument which asks patient to reflect on past painful experiences, and to indicate the degree to which they experienced each of these 13 thoughts or feelings, on 5-point scales with the end points; 0 = not at all, 4 = all the time. The PCS yields a total score and three subscale scores assessing rumination, magnification and helplessness (7).
* The Hospital Anxiety and Depression Score (HADS) is a 14-item scale, which screens for these, the two most common disturbances encountered in a medical setting (8).
