When and where: Gold Coast, Australia, August 30-31, 2008.
Attending group members: James Harrison, Kavi Bhalla, Jed Blore, Wendy Watson, Maria Segui-Gomez
What did we do: We made progress on the following discussion papers:
Discussion Topic 12 External cause recommendations: James and Kavi reviewed the comments received from expert group members since July 1st (i.e. since the last time summary recommendations were made) and updated the expert group recommendations on the topic. James wrote a short briefing document addressed to the central team summarizing the issue and the action expected from them. The detailed discussion document was included as an attachment and sent to the central team. Although we do not intend to update our recommendations to the GBD 2005 exercise again (unless the central team requests clarifications), we suggest that the injury expert group continue to provide feedback on the topic until October 15th, at which point we will summarize the recommendations and prepare the document for peer-reviewed publication. See our expert group website for more details (http://sites.google.com/site/gbdinjuryexpertgroup/ Click on the link for "Discussion 12").
Discussion Topic 3 Injury sequelae definitions: James, Maria, Wendy and Jed did the following:
It had become urgent to provide input to the Core Group on GBD sequelae definition. This is because the field work to generate new GBD 'disability weights' requires definitions and lay descriptions, and that phase of the project is about to commence. Four of us (James Harrison, Jed Blore, Wendy Watson, Maria Segui-Gomez) used the opportunity provided by being together to draft and discuss a set of definitions and lay descriptions, and to complete health state checklists, which were provided to the Cluster C leader, Theo Vos, after the meeting, for use in meetings of the Core Group the following week. We made use of preliminary work that some of us (Harrison, Watson, Blore) had done before the meeting. This work has implications for the case data extraction and analysis aspect of the project, because the 'GBD sequelae' categories for injury are largely specified in terms of ICD codes from the injury chapter (ICD-10 chapter 19; ICD-9 Chapter 18).
The starting point for this work was the list of 'GBD sequelae' categories used in previous GBD work, and shown in Table 3 of the GBD-2005 Operations Manual (pp 94-6). Priority was given to 'sequelae' that are likely to contribute greatly to estimates of DALY burden (e.g. TBI, SCI), but we also aimed to represent the diversity of injury. Each of the selected sequelae from Table 3 was considered by one member of the group, who completed a template document specifying the injury in terms of ICD codes, describing and discussing definitional and conceptual issues, presenting information and assessment about burden due to the condition and writing a short description of the state of having the injury. For some of the 'sequelae', we also completed a 'health state checklist', which is intended to enable the effect of the condition on a set of domains of functioning to be summarised. Writing the document and completing the checklist often raised technical or conceptual issues, which were discussed in the group, and the documents were revised. Some follow-up work was done in the days following the meeting. Be the end of this process, we had produced 12 documents which provide lay descriptions for more than 20 'GBD sequelae'.
In the course of doing this work, we found reasons to alter some of the existing 'GBD sequelae'. In essence, the issue is heterogeneity vs project practicability. Injuries can lead to a wide variety of states (defined in terms of health and functioning). Ideally, 'GBD disability weights' would be produced for each distinct state, but that would require a vast project. In reviewing the existing 'GBD sequelae', we considered whether there were compelling reasons to split, lump or reorganise them. The results of this can be seen at the web site. Some of the noteworthy proposed changes are:
- Intracranial injury: replacing 'short term' & 'long term' types with three levels of severity;
- Eye injury: replacing 'short term' & 'long term' types with three categories that focus on visual deficit.
- Spinal cord injury: split into quadriplegia and paraplegia and according to treatment status.
The documents have been placed on the Expert Group web-site at [ http://sites.google.com/site/gbdinjuryexpertgroup/ Click on the link for "Discussion 3" ] for information and for input form other members of the group. This work would benefit from wider input form the group. The need is URGENT: if you want to contribute to this aspect of the project, please note that the sooner you provide input (i.e. days rather than months), the better the chance that it will be in time to influence the GBD 2005 project. Contact james.harrison@flinders.edu.au about this.
The state descriptions, written to be intelligible to a lay reader, will be used in the field studies being led by Josh Solomon, to produce new sets of what, in the GBD project, are called 'disability weights'. We were given a brief overview of the study design at the workshop. In essence, sets of subjects in several countries will be asked to compare and rate pairs of descriptions, from a pool of 50 to 70. The 50 to 70 will be chosen from all sequelae in the project. This has not yet been done, and we don't know how many or which injury sequelae will be among them. The findings of a large number of pair comparisons will be used to place the 50 to 70 states onto a 0 to 1 scale. A second process, described very briefly as involving internet-based data collection, will be used to interpolate all other sequelae on the same scale.
Data Analysis Planning:
New sub-team: A new data analysis sub team was created for the expert group. At the Gold Coast meeting, the team primarily discussed analysis of hospital data but we hope to expand the scope of work to include analysis of mortality data, survey data and other sources.
Current members and how to join: Kavi Bhalla will lead the work on developing countries; Maria Segui Gomez will lead the work on the European regions (East, West and Central); Jed Blore will lead the work on all other high income countries from which data is readily available (to start with US, Australia and Singapore). The work of this team is likely to be analysis-intensive and so the current collaborators are members who can volunteer both data sets as well as substantial amount of people hours for analysis. Please do consider joining the analysis sub team if you think you can make such a contribution yourself. Otherwise, you may want to be included as a "lurking member" in these discussions – lurking members are copied on email conversations so that they can make suggestions.
Implications of the timing crunch: In order to maximize input into the GBD 2005 project, the data analysis will need to ramp up activity immediately. There are two pressing reasons for this: first, we need to send data extraction scripts to owners of administrative data. Second, the sub-team needs to produce a first set of incidence estimates by late November 2008 to send to the core team. For these two reasons, the team discussed the various methodological hurdles (e.g. handling multiple injuries) and decided on resolutions based on their current understanding. Since some of these issues are being dealt with as discussion topics that are still at an early stage of development, it is imperative that the authors of the relevant discussion topics closely study the plans of the analysis sub-team and propose changes where needed. The current plans of the analysis sub-team are described on the expert group website at : http://sites.google.com/site/gbdinjuryexpertgroup/ Click on the link for "Data Analysis".