The anti drain back valve is a definite issue. A lot of the GM trucks with V8 engines from early 90's up had the filter laying horizontially which allowed them to leak off the oil when the engine sat for any time at all. This requires the oil pump to fill the filter 1st before it can build pressure for the lifters and worse yet the bearings. I had a couple of those models and they all clattered in the morning when you started them. Especially in cold weather. Wix developed a new filter for these that had the anti drain back valve to prevent the oil from draining out of the filter. It stopped the clattering problem.
Keep in mind that the filters that have been tested in this study are the (or used to be) the top selling Ford and Chrysler filters. The FL1A (Wix 51515) was the #1 selling filter for all filter manufacturers for 20 years. In most cases this was the loss leader for the high marketing, low quality companies. If they are going to cut corners this is where they will do it. Companies like Wix, Baldwin, Hastings, and most heavy equipment oem's who are selling on quality and demanding the higher prices do not cut corners on any of their filter applications.
I saw quality studies like this done 15 years ago and the results were pretty much the same. I came to some conclusions then about what I will run on anything I own and what I won't. I will not run a filter that has a string tied around it. Maybe there is no problem with the string but it does not denote quality to me. I don't like a filter that using a spring steel insert for the pressure relief spring. OEM's typically don't manufacture their own filters so just because it says AC, Motorcraft, Mopar, or even John Deere does not mean it is a quality filter. I have cut open AC filters and found strings wrapped around them.
I am partial since I am a distributor for Wix but that is the only filter I run. If that is not available I will run a John Deere, Kubota, Baldwin, or one of the other primary heavy duty manufacturer's filters. It's a rare occasion that I can't get the filter I need in Wix. Wix also makes NAPA Gold, Carquest, and a few other private label filters. The quality is the same as long as you are buying the top line filter in that brand. Wix also makes a strictly light duty automotive filter called Protec which is the same as NAPA Silver. These are excellent filters for the price. I'd put them up against any Fram, Purolator, and the other high marketing, low price brands any day.
To summarize, oil and filters are cheap, engines are expensive. This is not the place to cut corners. If you pay $2 or $3 for a filter then you are most likely getting 2 or 3 dollars worth of filter.