The tests are used to assess the candidates in order to determine whether they match the proposed post.
It exists five types of tests: 
           Aptitude tests 
           Intelligence and logic tests 
           Personality tests 
           Projective tests 
           Potential tests

Aptitude tests are used to predict how well you can perform a particular job or task. They examine your potential by testing aptitudes that are relevant to the job or task in question. They are used to assess physical abilities and concentration faculty.
These tests are based on spacial awareness, verbal reasoning, numeracy, manual dexterity or hand/eye coordination and problem-solving. This type of test can be found in some questions of administrative examinations.

These are some examples of the most common tests: 
           the Bur1 and 2 
           technical skills 
           Wiggly block, it is a bit different but it is classified among the aptitude tests 
           Assessment center

Intelligence is a very hard notion to assess. Someone is considered as intelligent when he is able to find a solution to a problem he has faced. These tests carry out various problems based on words, numbers, symbols and several sequences.
This is the list of what is most common: 
             Progressive Matrices  
             The dominos 
             The sequences

These tests are often used for the recruitment of sales staff, executives or officers.
They are introduced in questions form ( from 50 to 500) that the candidate has to answer either : 
   by yes or no 
   by a scale of value (from "strongly agree" to "strongly disagree") 
   by MCQ
These tests are used to get a generalized overview of an individual’s character: 
           interpersonal 
           open-mindedness 
           organizational skills 
           resistance to frustration 
           conflictual reaction 
           etc.
For each trait, several question overlap. Each question puts the candidate in a situation by highlighting a trait in question. It is up to him to choose the suitable answer.
These are some examples: 
              The 16pf 
              The psychorater 
              The QWO (Heuyer-Courthial personality questionnaire)
              The EAE (The Self Esteem Test) 
              The WAE (The Weinstein Self evaluation)
              The alter ego (the five fundamental personality factors) 
              The Zimmerman and Guilford 
              The QPPL

They are very long and so much expensive to run. In addition, a perfect command of the results analysis will guarantee its genuine usefulness. 
These tests are designed to let a person respond to ambiguous stimuli, presumably revealing hidden emotions and internal conflicts. Therefore, the psychologist will introduce pictures, photos and  comic strips.
These are the most frequently used projective tests: 
               Tree testing 
               Rozenweig 
               Rorschach

Setting the standard for the professional milieu and considering the dimensions that are important for the entrepreuneurs, they are able to set a reliable basis for an appraisal interview in order to identify the strengths and the weaknesses of a candidate as well as his motivations and personal functioning.

A reliable test should be deliberately validated and should meet very high requirements such as:

­   Accurate definition of what is measured.
­   Sample of more than 500 persons for the reference population the total statistical validation.
­   Results constancy and predictive value
­   Consistency control and the non-manipulability of answers
­   Taking into account cultural factors.

These criteria rule out, mainly, any professional use of tools which have not been developed and tested according to these principles. Ces critères excluent, en principe, de toute utilisation professionnelle des outils qui n’ont pas été mis au point et testés selon ces principes. A great vigilance is therefore required.

The test should be an assistance to the decision. It should never lead directly to a decision. The result must be anyway validated during an interview and even confirmed by the concrete observations. The test can help the candidate to deepen his knowledge, to discuss openly sensitive issues questions and also to have an accurate opinion about the chances of success and the risks of failure. 

  Note:

1. Selections tests are numerous but very few meet the scientific criteria that are essential for validity and reliability.
2. The tests should only be an assistance to the decision: an interview is essential to validate objectively their suitablity.
3. Interpreting the results requires unfailing professionalism. The one in charge should know exactly what is measured and should put the results in the professional context of the post, of the team and the enterprise (chances and risks).
4. A total transparency must exist at the levels of results and the access to this latter must be limited. The ethics of applied psychology and the guidline on the data protection should be respected.