延宕交叉相關與縱貫中介模式在憂鬱、問題網路使用與生活型態改變之探討

Abstract

過度網路使用又被稱為問題網路使用 (problematic Internet use 以下簡稱PIU)，乃以美國精神醫學會第四版「心智失序診斷暨統計參考手冊」(Diagnostic and Statistical Manual of Mental Disorders – 4th Edition，DSM–IV，American Psychiatric Association, 1994) 作為定義的參考架構，過去研究者主張PIU可歸類於上癮症 (Young, 1998a) 或衝動控制疾患 (Shapira, Goldsmith, Keck, Khosla, & McElroy, 2000)。PIU被認為是一種衝動控制疾患，這意謂著在使用網路之前，個體會經驗到慾望上升的焦慮或警覺，使用網路後，則因慾望獲得滿足，焦慮得以釋放，產生愉悅感。本研究採用初級預防的觀點研究PIU，關注的是一般人過度涉入網路的初期條件，此時個體還沒有喪失適應性功能。因此，本論文的研究對象乃是針對所有使用網路的大學生，而非已經表現出具有嚴重沉迷症狀者，希望分析導致大學生出現問題網路使用行為的心理前提與生活功能後果。特別是過去研究已經發現憂鬱與問題網路使用有高度相關，但是孰先孰後的時序關係尚未有定論。再則，如果問題網路使用導致功能喪失，其衝動控制失序即逐漸發展成精神疾患，因此在學理上，病態網路使用與不健康生活型態之時序關係也需要進一步確立。本研究乃對於同一群大學生樣本從2008年11月起連續五個學期收集長期追蹤資料 (panel data)。本論文為三個連續研究，終極目標乃欲了解憂鬱、問題網路使用與不健康生活型態的影響關係，故於第一個研究中先發展設計一個篩檢工具，乃採用其中一個波段資料建立因素結構，下一個波段資料檢驗預測效度，證明此研究工具的有效性。接續於第二個研究中，分別探討憂鬱與問題網路使用，以及問題網路使用與不健康生活型態間的時序影響關係。且基於研究二之結果，利用三個波段資料建構出憂鬱、問題網路使用與不健康生活型態的縱貫中介模式。 第一個研究建構了一個新發展的一級預防篩檢工具以檢測問題網路使用及生活功能失序，命名為「問題網路使用導致生活型態改變」量表（LC-PIU）。進行探索性和驗證性因素分析以檢驗LC-PIU的因素結構後發現，LC-PIU有一個「問題網路使用」分量表及四個不健康生活型態分量表：「身體活動改變」、「社會活動改變」、「飲食模式改變」和「睡眠模式改變」。兩種因素分析結果均建議，五個因素的測量模式具有良好的信度與建構效度。此外也檢驗此工具的共同效度及預測效度，發現第一個時間點的五個分量表皆與第一個時間點及第二個時間點的憂鬱、寂寞和網路使用時間呈現正相關。其中，無論是第一個時間點或第二個時間點的性別與社會活動改變則呈現負相關。其次，由於許多研究者 (Campbell & Stanley, 1963; Kenny, 1975) 建議延宕交叉相關分析乃是一種準實驗設計方法，可以探究兩個時間點變項間的時序關係 (或準因果關係) ，因此，本論文的第二個研究目的乃是以縱貫分析研究觀點追蹤台灣大學生的憂鬱與問題網路使用，以及問題網路使用與四個生活型態改變間的可能預測關係。研究結果發現前一個時間點之憂鬱可以預測下個時間點之問題網路使用。問題網路使用與三種生活型態改變 (身體活動、社會活動、飲食模式) 間有交互時序影響關係。然而，問題網路使用與睡眠模式改變間為單向時序影響關係，亦即只有前一個時間點之問題網路使用可以預測下個時間點之睡眠模式改變。基於研究二的結果，唯有問題網路使用對睡眠模式改變有單向預測效果，且睡眠模式改變是大學生身心健康指標中非常重要的一項，對學習與認知有切近的影響力，是故第三個研究中問題網路使用的後果變項只採睡眠模式改變。本論文的第三個研究目的乃藉由縱貫中介模式處理三個時間點的追蹤小組資料，分析大學生之憂鬱、問題網路使用與睡眠模式改變間的時序預測關係。研究發現，問題網路使用確實在憂鬱 (前置變項) 與睡眠模式改變 (後果變項) 間產生中介效果，換言之，第一個時間點的憂鬱情緒會影響第二個時間點的問題網路使用，且第二個時間點的問題網路使用會影響第三個時間點的睡眠模式改變。同時，本研究進一步檢驗此縱貫中介關係，前置、中介與後果變項間的預測關係是否為跨時間恆等，研究發現，憂鬱對於問題網路使用的預測為跨時間恆等 (第一時間點憂鬱第二時間點問題網路使用 = 第二時間點憂鬱第三時間點問題網路使用)，而且問題網路使用對於睡眠模式改變的預測也皆具有跨時間恆等現象隨時間呈現穩定的影響關係。綜合上述三項研究結果，本論文提出大學學生課外活動、生活管理與輔導的建議，也對未來研究方向提出具體建議。

Excessive use of the Internet, often coined problematic Internet use (hereinafter PIU), resembles either the definition of addiction disorder (Young, 1998a) or impulse control disorder (Shapira, Goldsmith, Keck, Khosla,& McElroy, 2000) in the DSM-IV (American Psychiatric Association, 1994). PIU is considered an impulse control disorder which means that before using Internet, individual experiences rising tension or arousal; however after finishing the internet use, individual has a sense of relief or pleasure. This research adopts the position of primary prevention which generally concerns the prevention of mental disorder and conditions before their biological onset. Therefore, the focus of the dissertation is on all university students who use the Internet, not users who already show severe dependent symptoms. The dissertation aimed to analyze the university students’ psychological premise and functional consequences in daily life in regarded to PIU. Particularly, previous studies found that depression and PIU were highly correlated but the temporal ordering of depression and PIU have not been proven. Furthermore, if PIU causes loss of impulse control and gradually develops toward a mental illness, theoretically the temporal ordering of PIU and unhealthy lifestyles or lose of daily functions need to be further established. Therefore, this study collected data in a panel of university students starting from November 2008 for five consecutive semesters. Only two- to three-wave data were analyzed in this dissertation. The dissertation includes three consecutive studies, the ultimately goal aimed to examine the temporal relations among depression, problem Internet use and unhealthy lifestyles. Thus, the first study developed a screening tool of PIU. I tested factor structure of the scale with the data from one wave and examined predictive validity with the next wave. The second study was to separately investigate the temporal orderings of depression and problem Internet use as well as problem Internet use and unhealthy lifestyles with two-wave data. And based on the results of the second study, the third study constructed and analyzed a longitudinal mediation model about the relation among depression, problem Internet use, and unhealthy lifestyle with three-wave data. In the first study, a new primary prevention and screening tool, named “Lifestyle Change in Regard to Problematic Internet Use (LC-PIU),” to detect the onset of risk-taking behaviors was developed. I tested the factor structure of LC-PIU using exploratory and confirmatory factor analyses and found the LC-PIU was composed of a "problem Internet use” subscale and four unhealthy lifestyle subscales: “physical activity change”, “social activity change”, “dietary pattern change”, and “sleep pattern change.” The results of this two factor analysis suggested that the five-factor measurement model demonstrated good reliability and construct validity. In addition, the results of concurrent and cross-year predictive utilities showed that in Wave 1 all LC-PIU subscores were positively correlated with depression, loneliness, and weekly Internet use of Wave 1 and Wave 2. A negative correlation was found between gender and social activity change at Wave 1 and Wave 2. The second aim of the dissertation is to conduct two cross-lagged analyses that examined separate predictive relationships between (1) depression symptom and PIU, as well as (2) PIU and lifestyle changes from a longitudinal perspective. Many researchers (Campbell & Stanley, 1963; Kenny, 1975) suggested that cross-lagged analysis resembles a quasi-experimental design in verifying the relations of variables. The results showed that depression was a prospective predictor of PIU. The temporal relationships between PIU and three lifestyle changes (physical, social, and dietary lifestyle change) were reciprocal; while PIU and sleep pattern change showed a single direction effect: only precedent PIU positively predicted subsequent sleep pattern change. Based on the results of the study 2, because only PIU had unidirectional predictive effect for sleep pattern change which is a critical indicator of university students' physical and mental health, having immediate influences on students' learning and cognition, I chose sleep pattern change as the consequence variable of PIU. The third study adopted three wave points to examine the longitudinal mediation model of depression, problem Internet use and sleep pattern change. The result showed that PIU mediated the effect of university students’ depression and sleep pattern change. In other words, negative feeling of depression at Wave 1 predicted PIU at Wave 2 which in turn predicted the changes of the sleep pattern at Wave 3. I also further examined the time invariant effects of depression on PIU and the PIU on sleep pattern change. I found the effects of depression to PIU were stable across two periods (the path from Wave 1-depression to Wave 2-PIU was equal to the path from Wave 2-depression to Wave 3-PIU) and the effects of PIU to sleep pattern change were also stable across Waves 1-2 and Waves 2-3. Based on the integrative results of three studies, implications on the management strategies of campus activity, dormitory life and college students’ psychological wellness were discussed. Suggestions about future studies were also offered.