Scratch tests can be reasonably accurate, but not for every individual. My friend's test was a bust. It happens.
If you weren't tested for the widest array of foods, you might have missed some really bigs ones. If you don't eliminate those, eliminating other, milder allergies might not be so noticeable and make the test results seem more inaccurate than they are. Just saying that it's possible....
Whatever you choose (and I'm sorry I can't help you on the other kinds of tests) test as many foods as you can afford. It's pretty expensive, though. I think my extensive food tests would have cost $600 or more, I don't remember, without insurance.
It's not the accuracy of the test for a 3yo, but the changing landscape of allergies at that age. (Most allergists will test a 3yo child if they are having symptoms.) Most kids will outgrow their milk allergy before the age of 5, fewer will outgrow it later in life (me) and the rare child will retain a bonafide milk allergy throughout adulthood. My daughter picked up several new allergies, include one severe wheat allergy (numb tongue, the works) at about 3yo. So that's what you are facing with testing a 3yo. Doesn't mean you shouldn't test.
Does your child qualify for Medicaid coverage? In our state there are 3 tiers of Medicaid, and they cover all sorts of things like dental, orthodontal (sp?) psychiatric, etc. (And allergy tests with a referral.) Even if you don't qualify for yourself, your child might. Call your DSHS office if you think this is at all possible.
Give me a few minutes while I caffeinate.
I blog about our life with food allergies and eosinophilic disorders.
We have tried all kinds of elimination diets but I don't think that route is very effective for us, we need a test... We've never been able to get to baseline with eliminating.
I don't think we qualify for Medicaid but I will have my DH call just in case... I think with his unemployment checks, we are just above the cutoff point. I wish I could get some kind of inexpensive supplemental insurance.
Can you pick & choose which foods to test for? Does it make the most sense to test for every food possible? Or just the foods you eat most regularly? So we are currently on a vegan, gluten-free diet, should we still test for dairy, meats, etc? Obviously those aren't things that are causing us issues now since we don't eat them but if the results show lots of allergies then we may need to substitute in new foods and I've always suspected I'm allergic to certain animal products so I wouldn't want to sub in allergenic foods, you know? Maybe I'm getting too far ahead of myself but my sisters recently had testing done and found they were allergic to tons & tons of things & they weren't even having symptoms half as bad as mine...
OH! I'm guessing SPT is skin-prick test, is that right? So blood tests are actually less accurate???
The "casting a wide net" approach is loosing it's ground in the allergy world. May Drs are now going to "if you haven't seen a reaction we won't test for it". A positive result is only 50% accurate (a negative is 90+% accurate).
I see why one would be tempted to test a ton of stuff. I did 2 dairy trials with my first baby with no results because we didn't remove all his other allergens. BUT....I also know we took out way more than we should have. We got + result for things the a) are not common allergen and b) things we KNOW he wasn't reacting to but we trusted the first Dr. we went to (I have become much better educated on the subject now and would question his advice).
I agree 1000% with a food log and/or ED. Also, these tests aren't going to tell you if you/DH/DC are sensitive as CS has mentioned. Only "true" IgE mediated allergies (which are the ones responsible for anaphylactic reactions). A food log is more likely to catch intolerances and the like.
Are you/DH/DC experiencing things like hives? Difficulty breathing? Facial swelling? GI issues? Any combo of these are something I would speak to an allergist about. If not, I would really look into a very detailed food log to pinpoint your issues.
While not life threatening, there is a bevvy of other allergy symptoms that the general public are usually unaware of-- fatigue, frequent urination, confusion, adrenaline-rush type reactions, depression-like symptoms, reflexive coughing (like asthma, but from ingestion of food). I'm sure I'm missing a few. In kids, some of these symptoms wind up causing deep mood swings, sometimes violent outbursts in little ones. These symptoms are a big deal and can seriously affect your quality of life, even though you don't wind up in an emergency room.
Give me a few minutes while I caffeinate.