In a medical setting, we have seen a 10-fold rise in individuals identifying as transgender between 2011 to 2016 and similar rates are seen worldwide. Based on conservative estimates of 0.6 - 1.2%, we estimate that approximately 150000 - 300000 Australians may identify as trans and gender diverse.
We understand that in the 2016 Census, special procedures were introduced for the first time to enable a respondent to complete an alternative online form containing three response options to the Sex question: Male, Female and Other (please specify). This online form was available to households or individual respondents on an opt-in basis by contacting the Census Inquiry Service or submitting an online assistance request. This was incredibly challenging for transgender individuals and transgender community feedback was that they were unaware of the complex procedure to specify their gender identity. It also does not provide information on birth-assigned sex which is also important.
Some 1,260 people were considered to have provided a valid and intentional sex/gender diverse response (sex/gender because many did not give enough information to determine which). This is a rate of 5.4 per hundred thousand people - a very small proportion, and most certainly an inaccurate number of people with sex/gender other than male or female.
The decision to have this opt-in special procedure was implemented because of uncertainty about how the general public would respond to a question with an explicit 'other' option. This is not logical whatsoever as those that identify as cisgender male or female, would only select male or female. It is standard for most health services and businesses to have other options on gender forms, and in fact facebook has over 50 options.
Given fear of disclosure, collection of prevalence data needs to be at a census, population-based level and estimates from small cohorts (i.e. online samples, school samples) are inherently biased. Data on prevalence of those who identify as transgender will be enhanced with combination with other characteristics such as socioeconomic status, location of residence which will inform policy and health service delivery.