Table 2.

Five innovative studies about the pain after stroke research among the cited references of the included 322 studies.

Study	Sigma*	Journal	Study type	Sample	Intervention	Outcomes	Highlights
Adey-Wakeling et al., 2015	0.24	Archives of physical medicine and rehabilitation	A prospective population-based study	301	NA	Subjective reports of onset, severity, and aggravating factors for pain and 3 passive range-of-motion measures	The frequency of poststroke shoulder pain is almost 30%.
Zeilig et al., 2013	0.21	Pain	An observational study	30	NA	The thresholds of warmth, cold, heat-pain, touch, and graphesthesia	The more prominent sensory alterations in the shoulder region suggest that neuropathic factors play a role in hemiplegic shoulder pain.
Sprenger et al., 2012	0.17	Brain	An observational study	10	NA	Magnetic resonance imaging	The ventral posterior nucleus-pulvinar border zone is crucial in the pathogenesis of thalamic pain.
Kalichman and Ratmansky, 2011	0.17	American journal of physical medicine and rehabilitation	Review	NA	NA	NA	The authors categorized the possible underlying pathologies of hemiplegic shoulder pain into three categories: (1) impaired motor control (muscle tonus changes), (2) soft-tissue lesions, and (3) altered peripheral and central nervous activity.
Oh and Seo, 2015	0.17	Pain management nursing	Review	NA	NA	NA	Nurses should be knowledgeable of central post-stroke pain (CPSP), provide precise information to patients and their families, and develop effective nursing care plans that improve outcomes and quality of life for patients with CPSP.

^*Sigma = (centrality+1) burstness (burstness on the index) to identify innovative reference.