9: Workshop procedures - condition assessment
In the workshop, scores are given for three aspects of each parameter: 1) the condition in the worst-impacted 10% of the region under consideration; 2) the condition in the least-impacted 10% of the region under consideration; and 3) the condition in most (the remaining 80%) of the region under consideration. Each score is also assigned a confidence estimate (High, Medium or Low) as defined above.
The logic of selecting “10%” of an area for best and worst scores is justified for several reasons. Firstly, an area of 10% of the region under consideration has a higher predictive power than extreme examples of small spatial extent for detecting and/or resolving significant changes created by human activities. By looking at the worst and the best 10% of the region, both ends of the gradient are assessed, providing two independent measures and thereby constraining the “most” (80%) to a score within the identified range.
The scores are given based on grading statements that have been developed; these are general descriptive terms of the spatial extent, temporal extent, and magnitude of decline in condition of the parameters in relation to the selected benchmark. Each statement is associated with a range of numeric scores to guide the experts in reaching an agreed score for the parameter in question.
In addition to giving scores and confidence estimates, the experts will next judge the recent trend in each parameter as declining, stable or improving. The trends are assessed only for the last 5 years (and not in relation to the benchmark). The reason for this is to provide policy- and decision-makers with feedback on how policy responses have or have not had the desired effect. The choice of 5 years is based on the typical recurrence interval of SOME reporting in many countries and also because it is unlikely that measurable differences in condition could be detected in less than 5 years following policy changes implemented by government. A confidence estimate is also assigned to trends agreed by the experts (High, Medium, Low).