Analytica procedures and Substative test, if i can get a clarification on that and how the assertion

A substantive test is one which gathers evidence directly about a figure in the FS, that is not relying on the operation of controls. An analytical procedure can give some evidence that a figure is correct – or at least not out of line.

For example, if the receivables collection period last year was 40 days and is the same this year, then that gives some confidence about the receivables
figure.

Evidence is needed about each assertion a figure in the FS makes: eg valuation, existence etc for balance sheet items. Analytical procedures can give some evidence about each of these. For example, for non-current assets:

1 Valuation: compare last year’s depreciation charge to this years
2 Existence: compare book cost each year.

HTH