It has been almost two decades now since I took my first IT certification exams. The motivation behind gaining the sundry credentials has varied over the years, and the amount of time invested in preparation for a given exam has varied widely. After taking each test, however, I have always had a firm grasp of how well (or poorly) I understood the material being tested. Only two or three exams so far have resulted in a failing score, but there have been several that I passed by the skin of my teeth where my performance probably merited a failing result. The upshot is that the end score told me less about how well I knew the information than about the act of taking the test.

It never occurred to me just how little attention I paid to my own exam scores until recently. As the person who studied the material and took the test, there has never been any uncertainty about my command of the tested topics. Recently, however, I needed to evaluate the knowledge level of someone else who failed a certification exam. Then about four weeks later the individual passed the same exam with flying colors.

How much weight could I place in either result? In the end, I spent a great deal of time thinking about what a third-party can determine from passing and failing certification exam results. This article focuses on what can be gleaned from a passing exam score. Next month a follow-on article will focus on failed certification exams.

As a general rule, passing scores are all that employers will normally know about. An interview candidate is unlikely to mention that they required multiple attempts to pass a given exam. This is not a huge issue, although the reliability of a given test in assessing knowledge degrades somewhat as the number of attempts increases.

Even assuming the candidate passed the exam on the first attempt, the value of passing certification exams is a hot-button topic among certification detractors. A common refrain from the Certifications Are Worthless school of thought is that passing a multiple-choice exam is not proof that someone will be any good at a given job. Since I am a fervent certification advocate, it may be somewhat surprising to readers that I fully agree with that sentiment.

Picking one example, the Oracle certification program has created several "SQL Fundamentals"� exams over the years. They are some of the most commonly taken exams because a SQL requirement is part of several certification tracks. In addition, knowledge of the SQL language is an important skill for both Oracle database administrators and developers. In my opinion, the topics included in the Fundamentals exams are meaningful and cover most of the areas that an entry-level SQL developer should be knowledgeable in. Despite all of this, obtaining a passing score on the exam does not prove someone will be a good SQL developer for several reasons:

People Cheat Brain dump usage is widespread. They are so much a part of the certification landscape that I often see people arguing there is nothing wrong with using them. For this reason alone, you cannot be certain that a passing test score is meaningful.

Cramming Is Not Always Forever Many people are very good at memorizing a large number of facts in a short period of time, and then retaining those facts for a short period of time. It is certainly possible to pass certification exams without actually being able to make use of that data in the months and years after earning the credential.

The Real World Is Not Multiple Choice  The SQL Fundamentals exams, like most certification tests, consist of multiple-choice and multiple-answer questions. The question is spelled out clearly to the test taker. Immediately below the question is a list of possibilities that always contains the correct answer. In reality, you are seldom given a clear question to work with. The answers are almost never supplied. The real world is much more like an essay question ... except that it is often necessary to work with the person asking the question before it is even clear what they are asking for. It is virtually certain that some research will be required to locate the correct answer.

Knowledge and Skill Are Not Synonymous Knowing SQL syntax forwards and backwards does not ensure that someone will be skilled at writing complex SQL statements. Even if an IT professional has honestly studied the material in the exam, understands all of the concepts, and will retain it indefinitely, they still may not be any good at properly utilizing that knowledge.

So What Do We Know That We Know?

For all of the above reasons, a passing score on a certification exam is not absolute proof of someone's credentials for a particular area. By the same token, though, a four-year engineering degree from a prestigious university is not proof-positive that someone will be a good engineer. Both are just data points when making a decision about whether an individual might be a good candidate for a given job.

Despite this disconnect, fairly often on LinkedIn groups I see posts with titles that are some variant of "I just passed exam X with a 96 percent." The text of the post announces the poster's wonderful news and asks how they can leverage that high score to get a job. The truth of the matter is that employers in general have zero interest in how well candidates have performed on the exams related to these credentials. Even absent the analysis above, it is reasonably well understood that test scores do not map directly to performance.

For certification candidates, the truly important part of the score is that the inverse (i.e. 100 percent  95 percent = 5 percent) provides the minimum amount of the material that they really ought to be studying after the exam. Whether receiving a passing or failing score, test takers will benefit from going over the material again immediately after taking the exam. This is when they will have the best recall of the questions they did not know the answers to.