Sorting the respondents by incidence of Palmaris Longus we can see that, of the 193 respondents, the majority (77%) had Palmaris Longus in both wrists, with 13% having it in only one wrist and 10% missing it altogether.
Normalising based on the number of respondents in each category it appears that the rate of Dupuytren's Contracture is similar between groups.
Of those with Palmaris Longus bilaterally, 28% also had Dupuytren's Contracture in at least one hand; compared with 20% of those without Palmaris Longus and 9% of those with Palmaris Longus in one hand.
The age profile of respondents was spread between 16 and 72, but skewed towards the younger ages.
Normalising on the number of respondents in each age-group, it is appears that the incidence of Dupuytren's Contracture increases with age.
The respondents were 74% male and 26% female.
Normalising the sexes there is a similar incidence of Palmaris Longus, but slightly lower incidence of Dupuytren's Contracture in females.
Just over half of respondents had no preference in hold type; with crimps being more popular than slopers among those with a preference.
Comparing within these groups the incidence of Palmaris Longus is very similar, suggesting that it does not play a role in determining hold preference.
Respondents climbed at grades that were well spread over the scale, with the majority in the mid E-grades.
Normalising within grade-groups the incidence of Dupuytren's is mixed, not suggesting any strong correlations.
Frequency of climbing, showed most respondents climbing around three times per week.
Again, there was no strong correlation between frequency of climbing and incidence of Dupuytren's Contracture.