It probably sounds like a broken record, but the health care sector and its corresponding exchange traded funds are hot.

As has been reported throughout the week, health care ETFs have accounted for a significant percentage of the funds populating the new all-time high club. To be precise, 18 broad health care, biotech, pharmaceuticals, health insurance providers and medical device ETFs made new all-time highs Thursday. That number does not include a plethora of broad-market ETFs with significant and overweight exposure to the health care sector. [Biotech Weight Powers This Pharma ETF]

Two of the health care ETFs that notched fresh record highs yesterday were the Health Care Select Sector SPDR (NYSEArca: XLV) and the First Trust Health Care AlphaDEX Fund (NYSEArca: FXH). In theory, these ETFs should have wide differentials in performance terms despite tracking the same sector.

The reason being is that XLV is a cap-weighted ETF, ideal for the investor looking heavy exposure to blue chip pharmaceuticals stocks along with some well-portioned biotech and medical device exposure. On the other hand, FXH is one of the jewels of First Trust’s AlphaDEX lineup, a group of ETFs whose holdings are selected based on “growth factors including three, six and 12-month price appreciation, sales to price and one year sales growth, and, separately, on value factors including book value to price, cash flow to price and return on assets,” according to First Trust.

Surprisingly, the obvious differences between XLV’s and FXH’s respective methodologies has not created significant performances differences between the two ETFs this year as each is closing in on a 22% year-to-date gain. [Key Differences Among Sector ETFs]