There are now 433 million unique LinkedIn profiles, according to MarketWatch. Compare that to the entire United States population of just 326,625,791 to understand its staggering influence in business.

More than a third of Americans use it, which represents the majority of working people. That’s 40 percent of the population when you include children and seniors.

Most employers and candidates use LinkedIn. More than 90 percent of hiring managers search LinkedIn profiles for recruits. If you’re in such a position, but not entirely familiar with using LinkedIn to judge and compare potential candidates (whether they have applied for a position or you have performed a search), here is a quick guide to vetting the qualified from the unqualified, and the truthful from the deceitful candidates:

1. Look for Specific Job Histories

Unscrupulous companies help job seekers to embellish their LinkedIn profiles, taking advantage of how recruiters find candidates. For instance, a recruiter may search a keyword combination of “advertising account manager.” A candidate may show up who describes his experience as “I was the assistant to the advertising account manager for <name>.” If his LinkedIn title says “Advertising Account Manager,” this person may rank higher in searches.

To ensure that you are not being misled, verify job histories, including titles with the employers. Look for specific dates as well, and don’t trust profiles that include more than one defunct company (as these are often used to cover employment gaps).

2. Check for Valid References

You may have a quota of references for potential candidates. These same companies that fudge employment histories also use fake LinkedIn accounts to provide references. To spot invalid references, look at the location of the referring account and read the referral to see if it is pertinent to the skills you require. Vague references that read like a horoscope are a dead giveaway, as are references without a professional looking photo. Another easy way to spot this form of cheating is to see if a candidate’s references were all created at the same time. If the references pass these screens, see if you can find contact information to use later on in the interview process.

3. Look for Links from the Profile

LinkedIn limits the amount of insight a candidate can offer on a profile, but strong candidates enable potential employers to learn more through links to external resources. These candidates may have blogs, Twitter accounts, portfolio websites, and other examples of their work online to give you a sense of their accomplishments and skills.

Filtering out the poor candidates from the true contenders is a challenge, but these tips will go a long way toward determining fitness for interviews. Once you do contact candidates, obtain their resumes, references, and work samples to check against the information on LinkedIn.