colleagues raise the question of whether smoking could account for the lower bone density in women using depot medroxyprogesterone.4 We agree that smoking is a potential confounder and discussed this in our earlier publication.3 We are puzzled by Sharma and colleagues' reference to the two groups in our recent study. There were three groups. The control subjects certainly smoked less than the women who used depot medroxyprogesterone, but the proportion of women smoking was the same in those who continued to use depot medroxyprogesterone and those who stopped using it. Bone density increased only in those who stopped using the contraceptive. Finally, we note Sharma and colleagues' (unreferenced) assertion that measurements of the bone density of the femoral neck and wrist by dual energy x ray absorptiometry might be more accurate and reliable than measurements of the bone density of the spine. This is contrary to our experience and to most published data. We believe that the reason we saw greater changes in the spine than the hip is that the spine contains a larger proportion of trabecular bone and is more sensitive to oestrogen.

The concept of health gain is increasingly being used as a philosophical basis for the activities of health authorities, following the 1991 NHS reforms. A series of three multidisciplinary conferences were held to explore three health topics (coronary heart disease, antenatal screening for congenital malformations, and teenage planned parenthood) with respect to the management of health gain. A number of general issues are described which can be applied to any health problem. Particular issues include the importance of quantifying the problem using modelling techniques to identify nodal intervention points where an assessment of need for intervention can be made, problems in ensuring effective interventions are used, the necessity for intersectoral collaboration and the need to incorporate political reality into health gain management.

Highlights Abstract Background: Vascular access device insertion is one of the most performed procedures in healthcare today. With different device types available to provide infusion therapy, there are many different variables to consider, including the process of obtaining informed consent from patients. This literature review aims to discuss common themes present in current evidence-based practice and point out critical areas of variability that exist. Methods: A literature review was conducted searching Cochrane Library, Joanna Briggs Institute for Evidence-Based Practice, Cumulative Index to Nursing and Allied Health Literature, PubMed, and Google Scholar databases for recently published articles in the English language and those written in English. Articles were screened to include those that describe informed consent within the context of vascular access or other invasive procedures. There were 35 articles and 5 systematic reviews identified that met criteria for inclusion in this literature review. Discussion: The topics of ethics, legal responsibility, who provided consent, and how education about procedures was performed demonstrated clear insight into how to improve the consent process. Some areas in current evidence lack clear direction and create variability in the informed consent procedure. These included who should obtain consent from the patient and which vascular access devices required a written consent. Who obtains consent was found to be more related to current legal precedence and not the clinician inserting the device like that found when a nonphysician clinician performed the procedure. Vascular access device related variability in requiring written versus verbal consent was found to be rooted in the degree of complexity of the procedure, need for specialized training, and the inherent risk to the patient. Conclusion: These two areas of variability described in current clinical practice require more research and consensus agreement to standardize the practice of obtaining informed consent in vascular access device insertion.