The phrase "a deficiency which is" is correct and usable in written English.
It can be used when describing a specific deficiency or shortcoming in a particular context, often followed by an explanation or elaboration.
Example: "The report highlighted a deficiency which is affecting the overall performance of the system."
Alternatives: "a lack that is" or "a shortcoming that is".
One strain of canola, for instance, is rich in beta-carotene to combat vitamin A deficiency, which is still a problem in many developing countries.
For instance, Golden Rice was developed in 2000 with the goal to combat vitamin A deficiency, which is estimated to kill over 500,000 people every year (see this article).
He calculated that the loss of pollinators would place 71 million people into vitamin A deficiency (which is linked to child mortality) and 173 million into folate deficiency (which is associated with birth defects).
More than 250 million children suffer from Vitamin A deficiency which is a major public health challenge in more than half the countries on the planet -- with half a million going blind each year.
Vitamin A deficiency which is high among Ethiopian HIV-positive pregnant women [ 20] was first correlated with increased vertical transmission of HIV in Africa [ 67].
Research has shown that child deaths increase by about 20 per cent in population groups suffering from vitamin A deficiency, which is common in about 70 countries worldwide, most of them in Asia and Africa.
The only people in need of supplements would be those with vitamin A deficiencies, which are uncommon.
In addition, taking as little as 300 mcg daily may mask a B12 deficiency, which is relatively common in older adults, says Consumer Reports' medical director, Orly Avitzur.
Hence, our results are consistent with the weak excitotoxic hypothesis such that a bioenergetic deficiency, which is measureable in our mixed but not astrocyte cultures, allows normally innocuous concentrations of glutamate to become excitotoxic.
That same physician also hypothesized that the nightly use of Propofol accounted for the poor condition of Jackson's lungs while it was well known to insiders that Michael Jackson had a Tryptophan Synthetase Deficiency which is a lung disease characterized by a lack of protein for lubrication.
From the policy perspective, reducing an individual deficiency (which is poor OHRQoL in this context) to improve employment opportunities is only one aspect of handling social determinants of health; however, addressing poor OHRQoL cannot be discounted, especially when we now know that improving OHRQoL affects self-efficacy, which has long term positive impacts in general.
