It may apply moreso to US bond ETFs because of the regular income received. Every payment of a CDN listed fund will result in some currency f/x drag. Yes, there is a difference between corporate and government. There are various degrees of risk, with 'junk' corporates of course being higher than well-rated corporates. For both categories, the other risk is interest rate risk, and this is dictated by the average maturity or duration of the bond fund's portfolio. Longer maturities have more leverage to rates (both up and down leverage). Very short term bond funds have far less rate risk exposure. We would consider this a good primer.
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