Developing a Unified Theory of Information Security Behaviour in Nigerian Organisations: Integrating Protection Motivation, Social Identity, and Institutional Pressure

Existing theories of information security behaviour were developed predominantly in Western individual-centred organisational contexts and fail to capture the collective, social, and institutional dimensions of security compliance behaviour in Nigerian organisational settings. This study develops a unified theory of information security behaviour for Nigerian organisations by integrating Protection Motivation Theory, Social Identity Theory, and Institutional Pressure Theory into a novel integrated model. A sequential mixed-methods design was applied. Phase 1 conducted 36 qualitative interviews with security compliance personnel and end users across banking, telecommunications, and government sectors in Lagos, Kano, and Enugu to identify Nigeria-specific behavioural mechanisms. Phase 2 developed the unified theoretical model and tested it on a survey dataset of 680 employees across 12 Nigerian organisations using partial least squares structural equation modelling with higher-order construct specifications. The model introduces three original theoretical constructs: Collective Security Accountability (the influence of group security norms on individual behaviour), Institutional Coercive Compliance (regulatory pressure as a distinct motivational pathway), and Security Role Identity (security behaviour as an expression of professional identity). Available information security behaviour literature from African organisational contexts identifies collective rather than individual threat framing as the dominant cultural modifier of security motivation. Rogers' Protection Motivation Theory, Tajfel and Turner's Social Identity Theory, and DiMaggio and Powell's Institutional Theory provide the foundational elements. Findings demonstrate superior explanatory power of the unified model over constituent theories applied in isolation. Keywords: information security behaviour, unified theory, Nigerian organisations, social identity, institutional pressure.