Study	Reason for exclusion
Domar 2005	This study was excluded as there was no assessment of image quality. We, the authors of this review, believe that it is possible that the quality of the image could be compromised by the wearing of headphones while undergoing mammogram examination. This is because the patient can be asked to change position, hold a position, to gain best placement of the breast on the photographic plate in order to get the best image. The aim of this study was to determine whether listening to a relaxation audiotape before and during mammography decreases subjective reports of pain and anxiety. This was a randomised controlled trial of 143 participants. The participants were randomly assigned to a group that listened to a relaxation tape, a group that listened to music, or to a group that listened to a blank tape (control group). Though there were no statistically significant differences among the groups on any of the assessed measures of pain and anxiety, the authors concluded that the mean levels of anxiety and pain reported by the subjects were so low that it would have been difficult for any intervention to show an effect.
Everett 2005	This study was excluded as it did not have measurements on pain or discomfort in the control group, only the intervention group. The main aim of this study was to investigate if there was an increase in breast tissue acquisition following positioning training and the use of the Mammopad, the radiolucent breast cushion. The authors believed that the comfort provided by the pad would help women relax and co‐operate so that additional tissue could be acquired. Since their main focus was not on pain and discomfort, they only measured expected discomfort and experienced discomfort for the breast cushion group and not for the control group (no breast cushion).
Hendrick 2002	This study was excluded as the only available results were those from an interim analysis, and important information regarding randomisation was missing. We contacted the study author for further information, but have received no response to date. This study evaluated the effects of using radiolucent breast cushions on image quality, breast dose, positioning ease, tissue inclusion, and patient comfort. The only information available to us was an abstract detailing the results of an interim analysis with 29 subjects that was presented as a poster at a conference. This abstract reported that there was a statistically significant difference in comfort experienced with and without the breast cushion. Participants were imaged with and without breast cushions and, on a comfort scale of 1 (least) to 10 (most), the mean subject rating without breast cushions was reported as 4.2 (1.7) and with breast cushions was reported as 8.6 (1.5), P<0.00001). It was not clear from the abstract whether the numbers in brackets were standard deviations or standard errors and what statistical test was performed. It was also not evident whether the trialists randomised the breast that got the pad and, if so, how the randomisation was conducted.
Markle 2004	The main aim of this study was to determine if the use of a radiolucent cushioning pad on the mammography machine plate reduced the level of discomfort during screening mammography. This study was excluded because the first breast to be examined was always with the non‐padded plate, i.e. the allocation of the use of the breast cushion was not randomised. Other outcomes that were considered included any correlation between the reduction in discomfort and clinical factors, and the pad's impact on image quality, compression force, and radiation dose. The pads were randomly placed on the left or right breast but, as stated, the non‐padded images were always taken first. The mammogram consisted of images taken of the padded and non‐padded breasts in both CC and MLO views. The participants were asked to rate their level of discomfort after completion of the mammogram.
Nemergut 2001	This study investigated the effect of premedication with 10 mg or 30 mg propranolol, or placebo, on pain of mammography and associated anxiety. The researchers stated that they required a sample size of 360 to acheive sufficient power for this study. The research team had difficulty with recruitment of women and were unable to complete the study. They did provide us with a preliminary report of their findings. As the study was never completed, and included only 71 women rather than the 360 required for sufficient power, it was excluded.
Poulos 2003	The aim of this study was to determine the effect of reducing compression on breast thickness, reported discomfort and image quality. Each participant had an extra film taken, in addition to their normal routine films, with a compression force reduction of 10, 20 or 30 N compared to the normal film. The selection of the breast to receive the film was determined with reference to any evidence of breast problems, pathology or soreness. If any of these were present in one breast, then that breast did not receive the extra film. The participants were only asked about their level of discomfort once and not separately for the normal film and the extra film which makes it impossible to distinguish between discomfort experienced at the normal level of compression and that experienced at the reduced level of compression. This study was excluded as the selection of the breast to receive the extra film was not randomly assigned and separate measurements of discomfort were not obtained for the normal film and the extra film.
Tabar 2004	The aim of this study was to determine whether the use of a radiolucent cushion could significantly decrease the pain experienced during screening mammography without compromising image quality or other technical factors. This study was excluded because it was not a randomised trial, since the intervention (radiolucent cushion) was always applied when the right breast was imaged. This study had 838 participants. The radiolucent cushions were placed on the compression surfaces of the mammographic equipment and were used while imaging the right breast. No pads were used while imaging the left breast.