To correlate experimental data on the void swelling of metals and alloys induced by neutron, ion, or electron irradiation, a theory is needed that accounts for the process of intrinsic point-defect recombination with sufficient accuracy. This report shows that sink strengths for vacancies and interstitials can be derived in an analytical form if the equations of point-defect migration to sinks are linearized in an effective homogeneous medium. Such an approach permits the calculation of the void swelling rate and the bias factor for an arbitrary rate of point-defect recombination. Using the theory developed, fundamental parameters characterizing the capture of point defects by dislocations and voids are calculated from experimental data on void swelling and microstructure in pure nickel and copper irradiated with neutrons, ions, and electrons. The effect of dose rate on the temperature dependence of void swelling of pure metals and commercial alloys is discussed.