I probably don't need to provide most readers with too much background information on the topic of wandering/elopement and autism given the multitude of news reports that have been, and continue to be, generated on this worrying behaviour. The article titled: 'The Life and Death of Avonte Oquendo' pretty much sums up the very saddest outcome of wandering, and how in some respects, autism can potentially be a life-limiting condition.
I do however think it is important to discuss the findings reported by Bridget Kiely and colleagues  (open-access) and how science continues to contribute to questions such as "the prevalence and correlates of wandering in a nationally representative sample of school-age children in the United States with developmental conditions." I might add that I've seen very little in the peer-reviewed domain about wandering behaviour and autism here in Blighty (UK) or indeed, in other countries outside of the USA. Another important research inequality methinks...
The Kiely paper, which has itself received some press attention (see here), starts with the idea that as a result of the increasing numbers of people being diagnosed with an autism spectrum disorder (ASD) (see here) the likelihood that issues such as wandering or elopement will happen is going to increase. You can um-and-ah about the reasons for the increase in cases (bearing in mind findings such as the one by Russell and colleagues  talked about recently) but by mass action, increasing numbers of people with autism = increasing numbers of wandering/elopement episodes.
"Data were obtained from the 2011 Survey of Pathways to Diagnosis and Services (“Pathways”), a cross sectional, nationally representative survey of the parents and guardians of children with special health care needs (CSHCN) ages 6–17 with a current or past parent-reported diagnosis of ASD, ID [intellectual disability], and/or DD [developmental delay]." In all some 4000 parents and guardians of children with ASD, ID and/or DD were surveyed from a total population of some 7500. A proportion of those 4000 parents/guardians provided some data on their children incorporating elements from "the Children’s Social Behavior Questionnaire (CSBQ)." The issue of wandering/elopement "was assessed based on four questions about the child’s history of wandering from various locations within the previous twelve months" and data was divided according to diagnosis.
Results: "Among all children with a current developmental condition (ASD, ID, and/or DD), the overall rate of elopement within the previous 12 months was 26.7%." Readers should bear in mind the emphasis on elopement within 'the previous 12 months'. Further: "Compared to the ID/DD-only group, the odds of elopement were higher for the ASD-only group... and the ASD+ID/DD-group." This is based on participant groupings including: "492 had ASD-only; 924 had ASD plus ID and/or DD; and 2,085 had ID and/or DD without ASD."
The authors also observed that "children who were between the ages of 6 and 11 were more likely to have eloped than those that were 12–17 at the time of the Pathways interview" but there was little to see when it came to factors such as "household income, sex, or race/ethnicity." Elopement behaviour, it appears, crosses socio-economic differences. They did however report some associations between wandering behaviour and some of the clinical data reported using the CSBQ among other things. So; "wanderers were more likely than non-wanderers to show sudden mood changes...; to over-react to everything and everyone...; to get angry quickly...; not to realize when there is danger...; to have difficulty distinguishing between strangers and familiar people...; to be disobedient...; to panic in new situations or if change occurs...; to remain clammed up in new situations or if change occurs...; and to get lost easily." At this point I'm also going to introduce a new measure that also covers the topic of 'disappearing behaviour'  that might figure in future work in this area.
There is little more for me to say on this topic outside of the presented results. As I've indicated in previous posts (see here), in amongst all the 'differences' that divide people when it comes to the label of autism, moves to reduce the potentially devastating consequences of elopement/wandering when it occurs alongside autism seemingly unites everyone. Statistics that point to accidental death potentially including wandering as being contributory to early mortality in autism (see here) provide a stark message that investment in technology in particular, is an important area to minimise the potential adverse effects of wandering. Teaching skills such as those related to pedestrian safety  could also be a good idea. I might liekwise add that the involvement of water in several cases of death following wandering in relation to autism should also persuade policy-makers to provide something like free swimming classes to those on the autism spectrum?
 Kiely B. et al. Prevalence and Correlates of Elopement in a Nationally Representative Sample of Children with Developmental Disabilities in the United States. PLoS ONE. 2016; 11(2): e0148337.
 Russell G. et al. Changes in diagnosis rates and behavioural traits of autism spectrum disorder over time. British Journal of Psychiatry Open. 2015; 1: 110-115.
 Tyrer P. et al. The Problem Behaviour Checklist: short scale to assess challenging behaviours. British Journal of Psychiatry Open. 2016; 2: 45-49.
 Harriage B. et al. An Evaluation of a Parent Implemented In Situ Pedestrian Safety Skills Intervention for Individuals with Autism. J Autism Dev Disord. 2016 Feb 10.
Kiely, B., Migdal, T., Vettam, S., & Adesman, A. (2016). Prevalence and Correlates of Elopement in a Nationally Representative Sample of Children with Developmental Disabilities in the United States PLOS ONE, 11 (2) DOI: 10.1371/journal.pone.0148337