A couple of items to say about this first,
In most amphibians calcium can only be metabolized and used if there is sufficient D3 in the animal from exposure to UVB and/or dietarily. UVB supplementation is only effective if the lights are within 18 inches of the animal in question and the light does not pass through glass or plastic (so light from a window does not count). (Also ratio of A to D3 to E is important as these vitamins compete for uptake).
Simple calcium content is not enough to determine if there is sufficient calcium in the diet, the ratio of calcium to phosphorus also has to be taken into account. The ideal ratio is between 1 and 2 calcium to phosphorus ratio above that and you can get conditional deficiencies in other vitamins and the possibility of calcium salts forming in the digestive tract, below that and there is insufficient calcium.
That said, most soil (and as far as I can tell, only soil) arthropods have a positive calcium to phosphorus ratio (due to the high amounts of calcium in most soils (does not apply in most of out terraria as we use calcium low substrates like peat)) however what we tend to feed the frogs has a ratio of less than 1 calcium to phosphorus.
High calcium diets are possible to use to increase the levels of calcium but they have significant draw backs such as being labor intensive, increased mortality in the insects, and often only work for a particular life stage of the insect and are ineffective if there is insufficient D3.
For example, in crickets, the only stage at which a positive calcium to phosphorus ratio is achieved are pinheads, the crickets have to have the diet for 48 hours and only the high calcium diet as they will preferentially eat anything else, constant access to water (not fruit or veggies or they will not consume the calcium diets), and begin to die from the high calcium diet at 72 hours. (This is at 80 F (27 C), cooler temps mean you have to offer the diet longer and warmer temps moves the deadline for increased mortality up). Additionally the approximate times the calcium stays in the digestive tract is comparable to the length of time, the vitamin-mineral dust stays on the cricket.
Ed