How often have you gone through the interview process and evaluated the candidate only to find out soon after the onboarding process that the candidate is the wrong fit? It's frustrating when you realize that the candidate misrepresented himself or herself during the interview.

When this happens, it's often a failure of the interview process. Companies must have the right processes and questions in place, or risk ending up with the wrong candidate.

As we continue our special PPAI Expo week series, today we feature these insights from presenter Claudia St. John, president of Affinity HR Group Inc., who shares these five tips for conducting the most effective job interviews.

1. Prepare In Advance. Long before you are face to face with a candidate, you must have a clear vision for what the job requires and what skills, abilities and behaviors are needed for the role. Outline clearly those factors and craft the interview questions that will be most effective in assessing whether your candidate is right for the position. Make sure you know exactly what information and feedback you need to get out of an interview before ever going into one.

2. Structure Your Panel Interview. St. John recommends that all job interviews be conducted by a team of at least three interviewers. Panel interviews are critical because all panelists can witness the candidates' responses to questions asked. And when one interviewer is asking questions, the others can observe the candidates' body language, tone and, of course, response. If each interviewer knows his or her role and has the questions prepared in advance, each will be able to be much more present during the interview. Finally, each interviewer should have a specific area of inquiry and a set of questions, and should ask the same questions of each candidate so that all facets of the job are covered and the panel can truly compare candidates based on answering the same questions.

3. Use Behavioral Interview Questions. Research shows that the most effective way to structure a question is to ask it in the form of a past experience. For example, start each question with, "Tell me about a time when you had to …" or "Describe for me a situation when you had to …" As in most things, the best predictor of how someone will act in the future is how they acted in the past. And try to avoid questions that can be answered with a "yes" or "no."

4. Remember The "Rule of Thirds." She recommends following the "Rule of Thirds" which states that one-third of your hiring decision should be based on the experience and demonstrable skills that the candidate brings to the table, one-third should be based on how the candidate presented himself or herself during the interview process, and one-third should come from the results of a behavioral assessment test. We strongly recommend behavioral testing of all candidates because most employees fail in their jobs not because of aptitude, but rather because of their attitude.

5. Deciding On Your Candidate. As your panel of interviewers reviews and debriefs their thoughts of the candidates interviewed, be mindful to stick to job-related considerations. Did the candidate answer the questions sufficiently? Was the candidate clear and articulate, and present himself or herself well? Avoid areas of bias that can sway the hiring decision, such as the candidate's interests, hobbies, network of friends, cultural background or other non-job-related issues. Be sure to check with the candidate's references and to ask behavioral questions of the references, specifically if there are any areas of concern or lingering doubts that you have about the candidate. And, most importantly, even if you are pressed for time or are anxious to fill the position, do not hire a candidate unless you are absolutely certain that he or she will be a great hire. If, after the interview process, you are stuck choosing among a pool of mediocre candidates, start over. If you're in doubt, it's almost always best to move on.

Source: Claudia St. John, SPHR, is president of Affinity HR Group Inc., a national human resource consulting firm that serves as an affinity partner for PPAI members. St. John is an HR professional with 20 years' experience in global human resources, employee benefits, management consulting and communications. She specializes in strategic planning, employee engagement, organizational development, recruitment and executive career management.