Our Perpetual Pursuit of Precision 


SACS is one of the most predictive employee skill assessments available. That's no accident.

Each time a group of agents takes SACS, we compare their test results to their actual job performance data, making adjustments to SACS as necessary.

This validation builds on SACS' scientific foundation. We created SACS over a five-year period, comparing the test and job performance data of agents from a variety of job functions and industries.

Learn more about SACS validation and view our technical reports.  Request a SACS Demo.

Industry Services

 If our validation studies enhance the accuracy of our current tests, our diligent research of call center market trends ensures we don't leave anything out. We keep our finger on the pulse of today's agents, their responsibilities and the challenges they face every day.

A large part of our research includes surveys of call center managers and agents who perform numerous functions in diverse industries and settings.

With these results, we gain a greater understanding of the managerial landscape and what it takes to excel in a call center. We transform this information into refined testing and profiles that help you make even more accurate hiring and development decisions.

Validation Studies

Select International is committed to ensuring that SACS provides the highest level of accuracy and predictive validity. To this end, we conduct empirical validation studies on an ongoing basis. These studies evaluate SACS' performance and ensure it relates to important job performance outcomes (of all agent job functions) in the call center and help desk environments.

When SACS was developed, two different empirical validation studies were conducted to evaluate the performance of the system using a random sample of call center agents across different job functions and industry types.

After the initial analysis was completed, two additional studies further refined the product.

Select continues to conduct empirical studies for new and existing customers. To date, they have resulted in two SACS updates.

How valid is SACS?

The scientific term used to determine whether employee skill assessments are valid is 'validity co-efficient.'

View SACS' validity co-efficient results.

If you have not studied validation you may be asking "so what is a good correlation?" Here is a fun way to get an idea of how SACS stacks up: comparative correlations.



  1. Antihistamine use and reduced runny nose and sneezing. r=.11 (N=1,023)
  2. Batting average as a Major League baseball player and hit success on a given instance at bat. r=.07
  3. Effect of nonsterodial anti-inflammatory drugs (e.g. ibuprofen) on pain reduction. r=.14 (N=8,488)
  4. Post-high school grades and job performance. r=.16 (N=13,984)
  5. Nearness to the equator and daily temperature in the U.S. r=.60 (k=19,724)
  6. Relationship between gender and height for U.S. adults. r=.67 (16,962)
  7. Conventional dental X-rays and diagnosis of between-tooth cavities. r=.43 (k=8)
  8. Nicotine patch (vs. placebo) and smoking abstinence outcome. r = .18 (N=5,098)
  9. Sleeping pills and short-term improvement in chronic insomnia. r=.30 (n=680)

To put these correlations into 'hiring' perspective, extensive reviews of employment interviews indicate that structured interviews correlate with performance approximately r=.33, while well-designed, structured behavioral interviews correlate approximately r=.44 with performance.

Because differences in correlations relate to multiplicative vs. additive differences in predictive accuracy, the true difference in accuracy of SACS employee skill assessments in the worst case scenario is:

  • 4 times more accurate than unstructured interviews
  • 2 times more accurate than structured interviews
  • SACS Validity Co-efficient Results

    The following is an example of some of the SACS predictor score correlations with Job Performance.

    Overall Predictor JobPerformance Validity Co-efficient
    Study 1 - Customer A .55 *  
    Study 4 - Customer F .76 **
    Study 6 - Customer I .68 *  
    Study 8 - Customer M .57 **
    Study 9 - Customer O .70 **
    Study 10 - Customer R .48 **
    Study 11 - Customer S .89
    Study 12 - Customer T .52
    Study 13 - Customer U .79
    Study 14 - Customer V In progress
    Study 15 - Customer W In progress
    Study 16 - Customer X In progress

    * Correlation is significant at the 0.05 level (2-tailed).
    ** Correlation is significant at the 0.01 level (2-tailed).
    Note: Correlations are corrected for range restriction and unreliability