Salary Survey Extra is a series of dispatches that give added insight into the findings of both our annual Salary Survey and our smaller Salary Survey PLUS polls. These posts contain previously unpublished Salary Survey data.

There is, as they say, more than one way to cook spaghetti. Well, OK, actually they say something about cats that's not very nice and probably shouldn't be casually repeated. (There are spies for PETA everywhere, people.) And, you know, most people really only cook by spaghetti by throwing some noodles in a pot of boiling water, maybe with a pinch of salt for better flavor.

The point, irrespective of felines and pasta, is that there are generally multiple approaches you can take to getting stuff done. This is also true when it comes to preparing to take your next certification exam. There are many different ways to learn the material that will be covered in the exam, and certification candidates commonly use more than one method.

Are all of these learning approaches equally effective? It depends on you, but there are some tricks of the trade that are generally more relied upon than others. For example, boring old reading is the favored approach of many. Each year in our annual Salary Survey, we ask about the overall effectiveness of the various study materials that can be used.

Here's a look at what we learned from the 2016 Salary Survey. If you're comfortable using a variety of study materials, then you may find some guidance here by seeing what everyone else tends to find most effective.

Looking at the Does Not Apply column is particularly interesting, because it gives an indication of how many people do or do not use a given method. For example, more than half of all respondents had no use for either boot camps or community college courses. On the other hand, more than 90 percent of respondents prepare using both self-study books and practice exams.

Practice exams get a little more love than books in the Excellent and Very Good columns. And while roughly a third of respondents don't use instructor-led training, quite a few among those who do find it either Excellent or Very Good.

Online courses, MOOCs in particular, are widely acclaimed by industry observers. On the other hand, nearly half of Salary Survey respondents don't use them, though they do score fairly well among those who do.

What's your preferred method of training? Maybe you're making all the right moves, at least in terms of how your certified peers tend to operate. Or perhaps reflecting on the survey data here will inspire you to make a change.