If there is no issue number, place the colon after the volume number as in the example below.
Hex N, Bartlett C, Wright D, Taylor M, Varley D. Estimating the current and future costs of Type 1 and Type 2 diabetes in the UK, including direct health costs and indirect societal and productivity costs. Diabetic Medicine. 2012; 29:855–62. Table 1, Estimated UK prevalence of diabetes 2010 ⁄ 2011 and 2035 ⁄ 2036; [cited 2013 Jul 22]; p.858. Available from: http://onlinelibrary.wiley.com/doi/10.1111/j.1464-5491.2012.03698.x/pdf