Do children with selective mutism have fear of positive evaluation？

Socially anxious individuals are afraid of negative evaluation like criticism, ridicule, contempt and disapproval. In fact, Watson & Friend.(1969) measured such anxiety using the Fear of Negative Evaluation(FNS) scale.
  
Watson & Friend.(1969)  is as follows. 

Watson, D., & Friend, R. (1969).  Measurement of social-evaluative anxiety. Journal of Consulting & Clinical Psychology, 33(4), 448. doi:10.1037/h0027806.

Since Watson & Friend.(1969), Many researchers have studied the association between social anxiety and fear of negative evaluation. However, a research team consisting of Adult Anxiety Clinic of Temple University and Department of Psychology in Washington University developed The Fear of Positive evaluation scale(FPES) to assess fear of receiving praise in undergraduate students(Weeks et al., 2008).  

Weeks et al.(2008) is as follows.

Weeks, J. W., Heimberg, R. G., & Rodebaugh, T. L. (2008). The Fear of Positive Evaluation Scale: Assessing a proposed cognitive component of social anxiety. Journal of Anxiety Disorders, 22(1), 44-55. doi:10.1016/j.janxdis.2007.08.002.

Weeks et al.(2008) found the FPES correlated positively with measures of social interaction anxiety and fear of negative evaluation. The results of their study show that fear of positive evaluation and fear of negative evaluation are separate constructs. Therefore, social anxiety may be related to not only fear of criticism but also fear of praise.

On the other hand, many children with selective mutism are socially anxious or have social anxiety disorder(also known as social phobia). Although not every selectively mute child has high level of social anxiety, it is possible that they are afraid of positive evaluation. 

However, there is no research surveying fear of positive evaluation as well as fear of negative evaluation possibly underlying selective mutism. All we need is study！

Behavioral Inhibiton and Selective Mutism

Some children are innately predisposed to react to novelty with worries and anxiety. They tend to avoid new situations, places, and people. Some infants move their limbs vigorously in stressful cognitive tasks. Many, but not all, infants with these characteristics tend to become  behavioral inhibition, avoidant and anxious behavior to  novelty, in  his/her later live. Most important thing is that children with inhibited temperament will have social anxiety disorder and/or major depression or other psychiatric disorders as adolescent.

On the other hand, selective mutism is reckoned as a childhood anxiety disorder, although no conclusion has yet been drawn. But, given behavioral inhibition and selective mutism have childhood anxiety in common, I wonder whether selectively mute children is characterised by inhibited temperament or not. What percentage of children with selective mutism exhibit behavioral inhibition?