A spokesperson for NHS Greater Glasgow said: "During this by-election we have been keeping to the tradition of ‘purdah' – the rules governing conduct during parliamentary elections.We have declined a number of requests from by-election candidates to make a visit to the hospital part of their election campaigns.Visits to the hospital take up a great deal of time for the clinical staff members involved. Whilst we understand that candidates' intentions are not to disrupt patient care, the staff time taken up inevitably does impact on our services.In accordance with purdah guidance if we agree to facilitate a visit by one political party then we must offer this to all. Given the number of candidates involved in this by-election and the resources involved in facilitating up to nine visits to the Victoria Infirmary's A&E unit, we feel that in fairness to our staff and patients we are not able to agree to any requests."