It looks like the validity of this instrument is minimal, but not completely absent. This is not unusual for leadership instruments.

https://books.google.com/books?hl=en&lr=&id=807SCgAAQBAJ&oi=fnd&pg=PA210&dq=%22self+assessment+leadership+instrument%22&ots=psFYtrDpKR&sig=BVHNlm8DHGBiqPakRUQLz1isoVg#v=onepage&q=%22self%20assessment%20leadership%20instrument%22&f=false

I believe the following dissertation can be useful:

- Dennis, Robert Steven (2004) Servant leadership theory: Development of the Servant Leadership Assessment Instrument, Degree of Doctor of Philosophy in Organizational Leadership, Regent University.

UMI Number: 3133544

Could you write these items  and your inquiries about?

The point is that the original scale was developed by Yura (1970), and she proposed 5 categories or subdefinitions for these items (self, critical thinking and decision making, interpersonal relationships, gruoup relations, and job relations), but we can not find what items were supposed to be in each category...We are trying to adapt the scale (refined by Smola) into the spanish context...and this information would be helpful to guide our translation etc...

Dear colleague,

I think you have two choices complete each othe. First of all, to have a good translation for certain instrument, you should refine litratures review cover the used scale in specific then the leadership skills in general. This is followed by cheking content validity by an expert pannel then start your data collection. The second choice is to apply vadity test  that could be the confirmatory factor analysis on the already collected data.This test  will help attribute each item to its category.