Ten or more survey scale points are generally too many. We need to assign a weight, or definition, to each point on the scale. To do that for a ten point scale is arduous at best. Respondents may not read all the way through the “weights” and even if they did, would it make sense? For example, do you immediately understand what “slightly more than moderately agree” means? Respondents struggling to come to grips with a scale of this size might simply gravitate toward a middle or neutral point.
More than likely a large ten point survey scale will not have any weights assigned to it. This creates another problem: how do we know a rating of a “4” means roughly the same to two different people? The lack of consistency here means the resulting data will not be reliable. Unfortunately, the use of a ten point scale can undermine the validity of your data from the very start. You can avoid biased data by using a better, balanced scale. Best practice suggests using a forced choice survey scale of approximately six items. A scale of this size allows a range of response, but it also provides clear and distinct criteria or ‘weight’ for each scale point.